>> Unidentified Speaker:
From the Library
of Congress in Washington, D.C.
>> Fenella France: Good
afternoon everyone,
I am Fenella France, Chief
of the Preservation Research
and Testing Division, and
on behalf of our division
and [inaudible] Chief
of the Music Division,
I would like to welcome
you all today
for our Science Meets
Music: Technical Studies
of Musical Instruments
Symposium.
We have got a really
exciting lineup
and so I will introduce
[inaudible] and then let us flow
into the talks without
further ado.
The technical studies
of historical musical
instruments is not done
extensively in the field
and so it is fascinating
and just delightful to have the
speakers we have today brought
together to actually share
that information on some
of the research they are doing.
As part of an NEH, National
Endowment for the Humanities,
Preservation and Access Grant,
the work that has been happening
at the Library of Congress
along with our colleagues
at George Washington
and Catholic University is
highlighting the research of
and the study of glass
flutes by Claude Laurent
from the library collection--
Dayton C. Miller collection.
And these are some
really exciting research
that you are going to
hear about shortly.
Collaborations are such an
important part of our work
and we are delighted that within
this research [inaudible] we can
not only with colleagues in the
Music Division but also both
with George Washington
University
and the Catholic
University of America,
Vitreous State Laboratory.
The NEH grant has allowed us
to hire a two-year postdoc
and further collaborations
with other local institutions
have proved extremely rewarding
as part of that.
The Preservation Research
and Testing Division has
been working extensively
to expand [inaudible]
non-invasive instrumentation
as well as the application
of various instruments
to include the analysis
of a wide range
of heritage materials.
Of course, collections such
as music include materials
such as glass, metal, wood, and
a combination of organic plant
and animal materials
as well as inorganics.
This research into understanding
the degradation mechanisms
of many materials
necessitates this use of a lot
of complimentary analyses and
these have been a key part
of what we have been working
on in the lab ourselves
and we do really want to
acknowledge the techniques
that we don't have in
our lab and the expertise
of our colleagues who
are working with us.
I am going to go ahead and
start by introducing all
of the speakers at the
beginning and then we will flow
through the three talks
with the various speakers
and if one could hold their
questions until the end
of the three talks,
if you need to,
scribble it down on your iPhone,
but please if you [inaudible]
then can turn your iPhones off--
cell phones off.
So speakers of the first--
in the first presentation,
which is the Collaborative
Technical Study
of Claude Laurent's
glass flutes,
Carol Lynn Ward-Bamford
is the flutist,
and since 1993 has worked as
Music Specialist and Curator
of Musical Instruments
at the Library
of Congress' Music Division,
which oversees the
library's holdings
of approximately 2000
musical instruments for study,
performance, and exhibit.
She holds degrees in music,
performance on the flute,
and archives management
from Tufts University.
Stephanie Zaleski is a
postdoctoral scientist
at George Washington University
where her research focuses
on developing simple
noninvasive analytical tools
to study 19th century glass
and historic collections.
She obtained her
PhD in Chemistry
from Northwestern
University in 2016
and was recently a postdoctoral
fellow with the Department
of Scientific Research at the
Metropolitan Museum of Art.
Isabelle Muller,
is Project Manager
at the Vitreous State Laboratory
at the Catholic University
of America in charge of research
and development programs
for the US Department of
Energy (glass formulations
for Hanford Site tank
waste vitrification,
long term water leaching
of various waste glasses,
and development of
predictive algorithms
of the glass properties).
She obtained her PhD
in physical chemistry
from Pierre et Marie
Curie University in Paris
and was a postdoctoral
fellow in nuclear chemistry
at the Lawrence Berkeley
Laboratory.
Lynn Brostoff holds a PhD in
chemistry and Masters Degrees
in polymer materials
science and in art history,
and an Advanced Certificate
in Conservation of Historic
and Artistic Works, with a
specialty in Paper Conservation.
For the last 25 years,
Lynn has worked
as a conservation scientist in
leading museums and libraries,
including the Metropolitan
Museum of Art in New York,
and the National Gallery of Art,
the Smithsonian's Museum
Conservation Institute,
and most recently the
Library of Congress.
Jayme Kurland, who is at
the second presentation,
is a musicologist
and independent researcher
based in Northern Virginia.
She is currently
working on a project
with the music instrument
collection
at the Library of Congress.
Previously was the
Curatorial Research Fellow
in Musical Instruments at the
Museum of Fine Arts, Boston,
and a curatorial assistant
at the Musical Instrument
Museum in Phoenix.
Jean-Philippe Echard
is a curator
of bowed string instruments at
the French national collection
at the Musèe de la
musique in Paris.
He has studied musical acoustics
at the Conservatoire National
Supèrieur de Musique in Paris,
please excuse my pronunciation,
and was a Research Fellow
at the National Gallery
of Art in Washington, DC,
and the Laboratoire de
Recherche et de Restauration
of the Musèe de la musiqe,
developing methodologies
for the observation and
the analysis of materials
of musical instruments.
His PhD research was on the
materials and techniques used
to varnish musical instruments
from 15th to 18th centuries.
The three titles of the talk,
as I said the first talk
by the first four speakers
Collaborative Technical Studies
of Claude Laurent's glass
flutes, The Auloi of Meroë:
Preserving and Interpreting
an Ancient Musical Treasure
by Jayme Kurland,
and recent research
on Stradivari Instruments
at the Musèe de la musique
in Paris, Jean-Philippe Echard.
As I said we will hold all the
questions to the end of that
and I now with pleasure handover
to our first presenters.
[ Applause ]
>> Carol Lynn Ward-Bamford:
Good afternoon,
welcome to the Science
Meets Music.
As Fenella introduced, I
am Carol Lynn Ward-Bamford
from the Music Division
at the Library of Congress
and I am delighted to be
a part of the team setting
and presenting today's
Collaborative Technical Study
of Claude Laurent's
glass flutes.
I am incredibly grateful
to the Library of Congress
and its Preservation
Directorate,
the National Endowment
for the Humanities,
and my fellow collaborators
at George Washington
and Catholic Universities.
And without a doubt my deepest
thanks goes to the donor
of the flute collection,
Dayton C. Miller,
whose inquisitiveness
intersected with his professions
in music and science and his
flute collection continues
to inspire.
So a little background,
a few years ago,
on what seemed a normal day for
me at work at the flute vault,
I had pulled up a drawer and
searched the drawer to look
at some of the 18 crystal
flutes that we have,
and I realized they
weren't all crystal clear,
some appeared foggy.
I quickly shut the drawer
and thought was I
storing them incorrectly,
what was it in the glass
that was causing this,
how long has this been going on?
I peeked in and again I
wondered what was I going
to do about this?
Fortunately, I had met Fenella,
a scientist and a flutist,
and soon thereafter Lynn
Brostoff and I began working
on our historical
and technical study
of the Laurent glass flutes.
This involved a new assessment
of the flutes and understanding
of the flute maker,
Claude Lauren,
his manufacturing methods,
the causes of the fogginess,
how to arrest the causes, and
how to stabilize the flutes.
In 1806, Claude Laurent of
Paris invented and patent a
"flutes en cristal"-- in
crystal or of crystal,
a material he claimed was more
stable than wood and ivory,
which were currently
popular in flute manufacture.
He made the flutes
between 1805 in a variety
of materials, key
work, and colors.
The location of his
gallery is depicted here
in the Palais-Royal, which was
bustling with other craftsmen,
including his silversmith,
one of them Jean Dupont.
The flutes were extremely
popular and sent
to quite a few world leaders
including the one we held here
in the Miller collection which
was sent to President Madison
on the occasion of
his second term.
Prior to our research
and despite the appeal
of the Laurent flutes, little
was known or understood
about the glass flutes or
the maker or his workshop.
We uncovered his town of birth,
his baptismal day,
and his death day.
We also created a
website and database
of approximately 185
flutes known or manufactured
on building upon Dayton C.
Miller's original list of 40,
and through technical analysis,
we also uncovered the
composition of the glass
but more on that later.
And now meet the
collector, Dayton C. Miller,
where a scientist meets
musical instrument.
Miller was a flute fanatic,
a flutist, a flute composer,
a flute maker, a flute
researcher, a flute collector,
and a scientist at Case
Western for over four decades.
His careers in acoustics and
physics led him to experiment
with the acoustics of sound
and here he is depicted
in the middle in the
invention of the Phonodeik.
He invented this with which he
studied the overtones produced
by flutes of various materials.
Also showing here is the
picture from one of his ledgers
with detailed observations
that he took on all
of his flutes including
the glass flutes.
Along with his huge archive of
flute-related correspondence,
books and photographs, which he
donated to the library in 1941,
and his 1925 publication
on the flutes of glass
and that started us on our
journey that continues today.
And now I will turn this story
of the journey over
to Stephanie.
[ Background Discussion ]
>> Stephanie Zaleski: Okay.
I assume everyone
can hear me okay?
Good, all right.
So in spirit of Dr. Miller who
I would also want to add was one
of the first American scientists
who experimented with x-rays,
which is really interesting.
We undertook the
study, Technical Study
of the Laurent flutes.
Here on the slide, I have an
example of one of the ones
in the collection, and as
you can see, there is a--
this fogginess that Carol Lynn
talks about but it also varies
in joints, so something that
we needed to take into account
when we were actually
doing the analysis.
So undertaking this,
we had the goals
of understanding
how these were made.
Again like Carol Lynn said,
these weren't really
studied before so that is one
of the things that
we [inaudible].
We also wanted to know what
these flutes were made out of
since they were supposedly
"en cristal".
We also are assessing the
condition using microscopic
examination and this
all contributes
to determining what the causes
of glass deterioration are
as well as the different
types of risk factors
that we can experience,
and we were fortunate
to have an NEH grant from the
Preservation and Access Division
to create a simple
analytical toolkit
that can help us assess
glass type and condition.
And so pertaining
to our question
of how these flutes
were actually made,
I hope that the animation
that I have
on here is actually working.
We brought two flutes that
were made in 1819 and 1828
to the Radiology Department
at the George Washington
University Hospital.
And what is really amazing
about this technique is
that here you see 0.6
millimeters slices,
axial slices, and the data taken
for these two flutes was
actually done under two minutes.
And so what I show here is I
have a program that I developed
where it detects circles, so
you have an inner diameter
and an outer diameter, and
the plot below the animations,
again that are just scrolling
through the head joints,
so it's really amazing as you
can actually see the tone holes,
you can see the ridges, but what
is amazing here is despite the
fact that these were made
almost a decade apart
that the calculated
inner diameter is
about 17.9 millimeters.
And if we move on to
the upper body joint,
you can see that there is a
very regular stepwise decrease
in the inner diameter of the
joint and the interference
that you see in 1819 is actually
because the metal fittings
and keys on the flutes actually
produced slight interference
in the CT scan.
Regardless, we started off
at around 17.5 millimeter inner
diameter working the way down to
about 14.5 in exactly
half millimeter steps.
So this tells us that these
flute makers knew exactly what
type of sound they were trying
to produce and they had a method
for actually fabricating
these instruments.
And just again to really
drive that point home,
with the lower body joint,
we see a same exact trend
where the measured inner
diameter of these starts
around 14 millimeters and,
in half millimeter steps,
goes down to about 11.5.
So it's really amazing because
what we can now do is use this
information to reconstruct
the idea about the tone
and the sound of
these instruments,
and we are also looking
at hopefully scanning earlier
flutes as well as later flutes
to see if there was a change
in the manufacturing process.
So, of course, not
only are we interested
in understanding how they were
made but what they were made
out of and here I show the two
major techniques that we used
to determine composition
of the Laurent flutes.
We can use UV light and I will
show these are just two head
joints under visible light, but
if we use a UV light source,
different metallic species
in the glass will
fluoresce certain colors,
and with non-invasive
x-ray fluorescence,
we can actually get an
elemental fingerprint
without actually
having to take a sample.
And so under UV light,
you can see
that these head joints are
very clearly different,
and so 611 has this
characteristic green yellow
color, which is indicative of
manganese used in the glass,
which was actually used
a decolorizing agent due
to the iron in some of the
raw materials for the glass.
And the pink color of 378,
which is actually the head joint
of the-- what we call the James
Madison flute is indicative
of there being a leaded
or crystal formulation
in the glass.
And you can see that the
labeled elements that we have
in the x-ray fluorescence
spectra agree very well
with what we find with our
eyes using the UV analysis.
And so analytical techniques,
especially these simple ones
that we are trying to develop
can help us understand how
composition actually relates
to observed deterioration.
So, in the Dayton C. miller
collection, this fogginess
that Carol Lynn talked about
is actually the endemic symptom
of advanced glass deterioration.
And in this very
extreme case for 717,
you can actually very
visibly see it with your eyes,
you can see some cracking,
you can see spalling,
which is actually a loss of the
uppermost reacted glass layer.
But here I just want to
outline some of the techniques
that we are exploring
to actually really get a
quantitative understanding
of the observed glass
deterioration.
So we can use a technique
called FORS,
which is Fiber Optic
Reflectance Spectroscopy,
is a molecular fingerprinting
technique
and here we are interested
in peaks that are associated
with water and hydroxide,
which is actually a marker
of glass deterioration of
this silicate SiOH network.
We can all see the surface
pH because with the formation
of hydroxide you will
have an increase in pH,
so a more alkaline
environment on the surface,
and that just shows
with increasing pH,
we know that there is more
progressive deterioration.
And lastly, using
the expertise of GW,
we are doing image analysis.
We are actually trying to
give a quantitative measure
to texture rather than just
using a qualitative assessment
by eye and so different degrees
of cracking or different types
of features will actually give
you a different quantitative
measure of texture.
And actually we found that we
can use the non-invasive XRF
to give us an understanding
about if there is a reacted,
deteriorated surface layer.
So here I show a chip taken
from one of the joints of 717,
which Isabelle will elaborate
on in the next section,
but you can see that there is
a darker layer on the surface
of this in cross-section
and this is actually an
alkaline depleted surface layer.
And if you look at the potassium
composition of the bulk
versus the surface that the
XRF measurements actually very
closely match that to what we
calculate with the surface,
and this is because the
noninvasive XRF is actually very
surface sensitive.
For light elements
such as potassium,
the depth of the sample that
you are actually looking at is
on the order of about
20 microns.
So, because this is
surface sensitive,
we can usually use
this as a factor
of determining deterioration
in these potash glasses.
And so now that we have all
these data, we actually need
to do something with it, so here
I show sample data for flute 717
in the Dayton C.
Miller collection.
As you can see for each joint,
so it goes from head joint
to foot joint and
the extra joint,
we have all these
different variables
such as the surface pH,
the glass composition,
which includes the percent
surface potassium is what we are
calling it and then other things
such as calcium, manganese,
iron, lead, and rubidium as
well as the intensity of one
of the peaks that I have shown
in the Fiber Optic
Reflectance Spectra.
We are also working
to incorporate the quantitative
texture measures right now,
so we can take this
data and we can actually
perform different types
of statistical analysis in
order to pull out trends.
So here we are testing
out a technique called
principal component analysis,
which sounds very
fancy and complicated
but essentially what it is
doing is telling us what kind
of variance there
is in our data.
So we can input as many
variables as we like,
but just for this example,
I show flute joint,
the surface pH, the surface
potassium and the calcium
that were calculated by XRF.
So essentially having the
flute joint forces each kind
of cluster-- linear cluster to
be per joint, and so the plot
that I have here of the first
three principal components
describes about 90% of the
variance and variability
in the numbers that we
see in this database.
And so we see by
these blue lines,
which are actually
vectors, which tell us
about how each variable
contributes to the variance
that we observe that
they are actually going
in opposite directions.
So this actually implies
that the pH and the surface--
the calculated surface
potassium are inversely related.
So, if we actually go down
for each liner joint cluster
and do a relative ranking, we
can see that there is a decrease
in the pH and increase
in potassium,
which we are now working
on actually seeing
if how the ranking compares
to previous qualitative
assessments by a conservator.
In addition, this is
a separate technique,
but what we are doing is--
can we actually predict the
condition of these flutes
by using a cluster analysis.
So, again, here we have a
relative ranking now based
on a more quantitative
understanding of the data
such as the surface pH, the
potassium, and the degree
of micro-cracking that we see on
the surface and we can give it--
essentially what is
a score in this case.
And you can see that
the red points,
which are what we consider
to be unstable glasses,
do cluster out fairly well from
the at risk or stable glasses.
And we see, you know,
again, what I showed
in the previous slide is
that unstable glasses
have low surface potassium
and typically more alkaline
pH. And running this
through a classification
predictive creating a model,
so far we have been
able to obtain
about 80% accuracy from this.
So this is a really
promising way of, you know,
creating a database of what we
know to be deteriorated or not,
being able to share this
information with other folks
that have these types of
instruments is really valuable
for preserving these
collections.
And we are hoping
that the model studies
that Isabelle is
now going to talk
about will further inform our
assignments of these rankings
and really have a feasible
understanding of what is going
on with the deterioration
in these flutes.
>> Isabelle Muller: So,
the fun started for us
at the Vitreous State Lab of the
Catholic University in the fall
of 2014 when, you
see on this image--
on this photo, my
colleague, Dr. Buechele,
sitting at the microscope
and taking a little sample
of 500 micron-- that
is a huge piece
of this flute, two little chips.
And we actually included in
the fun, a high school student
who worked with us all year
long during her senior year
as a high school student
in Montgomery County
and that was really
exciting for her as well.
So this is flute 717, the one
that Stephanie showed
you earlier
and you can see where
we sampled.
This is taken at the very
bottom of the "v" groove,
the creative grooves
that you have seen
in the larger photo
of the flute before.
We were also able to
sample from another flute
which was not showing any
sign of damage in terms
of chemical alternation
but there was extra flute
joints that we could sample.
You can see here a scouring that
helped us take this whole piece.
So with this huge piece of
over 50 milligram of 1235,
we were able to take multiple
corroborative analytical
measurements as well as scanning
electron microscope analysis.
But with the duplicate analysis
we were making sure we were not
missing any element in the
composition of this flute.
And then, of course, we had
those two little chips of 717
for scanning electron
microscope as well.
What we learned then
with those tiny chips is
that this glass is simply
potassium silicate with 2%
of calcium and a lot bit of
sodium, absolutely no lead.
This is not surprising
because in the 1800
to 1850s there was a glass
that was extremely popular
because it was very brilliant
and very hard and very easy
to do nice decorative
engraving and that was known
as bohemian crystal, not
what we call crystal today
which is leaded.
We also were able to
do a nice polishing,
so this is a back
scattered image
of the two little chips of 717.
You are looking here at
the top part of the sample.
So this section is what
the exterior of the flute
and then this is the
interior of the flute,
and here in this very
nicely magnified image,
you can see clearly
that the surface--
the upper surface of the flute
has about 30 micron of a layer
that is of a different
composition.
And this is what happens if you
look at the chemical composition
of each of those
spots we analyzed.
Coming from the outside
with 2.5 micron spots,
we can see that the potassium
is very much depleted,
around 5 atomic percent by
weight here and it rises
to about 16 in the core of the
flute, we have a sharp rise;
same depletion with the sodium,
so both of those alkali depleted
in the surface as a result
of the so called leaching
of the glass or reaction
with humidity.
While this is a well
known phenomenon,
which we call the
interdiffusion,
so here I have a little
cartoon of a glass structure
which is the silicon
and the oxygen in red.
Those oxygen that
link the silicon
to each other are what we
call the bridging oxygen
and then some of those
oxygen are remaining open
so that they provide
charge balance
to what we call the glass
modifier, the sodium,
the potassium or the calcium.
And what is happening is the
water makes available a proton
that is going to sit in place
of this alkali causing it
to diffuse outside with the
equations I have marked here.
And you can see that as a result
of that you will have a slightly
increased pH at the surface
and that is what we see.
[background discussion] So now
that we understand what
is happening in the flute,
we want to try to
replicate it in the lab
so that we can play games
because unfortunately Carol
Lynn is not giving us the flute
to play with, more
than the 500 micron.
So of those two flutes
that we have here analyzed
in the first two columns,
we made three replicas--
I say replica because
they really include all
of the minor components of
the 717, high in potassium,
the 1235, and another flute
that is high leaded glass.
But we also bridged the gap
between 717 and 1235 with steps
of half percent potassium.
And this is the table of all
the composition we measured
to verify that we actually made
the glass we wanted to make.
This is how we made it-- this
is Rhea [assumed spelling] our
intern making the glass.
All of the ingredients are
put in a platinum crystal ball
at 1450 Celsius for
up to 4 hours of melt
and then the crystal ball
is quenched into cold water
to avoid any crystallization
of the glass melt.
And this very fast cooling
induces stress in the glass
that will cause it
to spontaneously break
into tiny pieces.
So we take those tiny
pieces and we put them back
into a [inaudible] crucible so
we could create a thin slice--
it looks like a coin of
about 3 millimeter thick,
which we have very
carefully annealed
so that we could
cut small coupons
that we will be using
in the lab.
And this is the result of
our little games in the lab.
So what you are looking here
are scanning electron microscope
of each of those little
coupon here is now mounted
in cross-section and then
we will polish it until
we expose the surface
and we can see what
has been happening
to the glass in cross-section.
So the black part of each image
here is where the exposure
to the air and the
humidity takes place.
It's actually mounted in epoxy,
so it gives a black image here.
We have two techniques of
accelerating the response
to water aggression or leaching,
the environmental chamber
or the vapor hydration test.
We started with the vapor
hydration test because we wanted
to see in a very aggressive
environment, but when you speak
of aggressive, this is
a test that was designed
about two decades ago for
testing the glass formulation
that was designed for
the nuclear waste glass
and that was supposed
to demonstrate the
glass will be good
for a scale of a million years.
So what happened is the
test is normally conducted
at 200 Celsius and a
100% relative humidity,
and in just a matter
of a few days,
this can of glass was gone.
So we decreased a little
bit the relative humidity,
still we have results
in one or five days
that shows a very
complicated structure
of the alteration layer, very
different from what we see
in the flute fortunately and
100s of microns of alteration.
So, on the other hand,
the environmental chamber,
90 Celsius and 90%
relative humidity,
gives us a much nicer
view that does compare
to what we have seen in 717.
In one day, in the environmental
chamber, we see 3 micron
of reacted layer; in
seven days, 65 micron,
and we can also do an analytical
profile here on the spots
of the electron dispersive
spectroscopy,
which I plotted here against the
717 I have shown you earlier.
So, this is the real flute
here, which after 200 years,
is about 30 micron altered.
This is our lab replication
in one day or three days,
seven days unfortunately is
going way up there, 63 microns.
So now, we will concentrate
on environmental chamber
coupon prepared between three
and five days so that we could
replicate what we have observed
on the flute.
We have some excellent
linear fit of the result.
The response of how much
of the depths of alteration
as a function of time are
all very liner and we can see
that as you move from the
lower potassium content
to the higher potassium,
the kinetics increase.
Well that increase is
actually a response of--
so this is my low potassium
from one to seven days
and this is my high potassium.
With only 4% increase
in potassium,
you have actually a response
that is a quadratic response
of potassium, so a square
of how much you increased
the potassium,
which is very important.
Unfortunately, the VHT
test was too complicated.
We were not able to
really use those results
to simulate the flute.
It showed us that there is
some effective separation.
However, what was very
useful is we could see
that the leaded glass was a
much slower type of reaction.
So, now, we can concentrate
on that same leaded glass
in the environmental chamber.
So these are our findings doing
all of these tests in the lab
and now I can let my
colleague Lynn [inaudible].
>> Lynn Brostoff:
Thank you Isabelle.
So, as Isabelle mentioned, the
VHT tests were very aggressive,
and when we looked, we
wanted to come a step back
and see how does
this experiment--
will work in the lab compared
to what we are really
seeing on the flutes.
And so what I show here
are some images we took
under the microscope of two of
the flutes and then images just
of the coupons not in
cross-section obviously.
And those images on
your right are samples
that were aged artificially
in the environmental chamber
and we were quite excited,
jumping up and down,
when we saw that the cracking
patterns looked so similar.
So this really supports
exactly what Isabelle was saying
about that these model studies
appear to be good replicates
of what we are seeing naturally.
And I point out that there is
a difference between one day
and seven days aging in terms
of the actual cracking
pattern going from a kind
of very fine cracking
to then what looks
like a much denser
network of cracking
and also separation
between the cracks.
So this looks consistent with
what we are seeing on the flutes
in terms of what we may term an
earlier stage of deterioration
versus a more advanced stage.
And you may be thinking in your
head, oh yes, that is crizzling,
well with a very common term
used in the conservation field
to describe glass deterioration.
And we have looked at quite a
lot of flutes with many people
and we found that everybody
had a different idea
about what crizzling
really means,
so we are just throwing it
out and we are going to try
and use some more
descriptive language.
Again stepping back at what
we actually see on the flutes,
as I said this very light
cracking does appear
to be consistent with what
we could term an early stage
of deterioration,
however, we-- as I said--
we have looked at
quite a lot of flutes
and it is actually very hard to
make these condition assessments
with your eyes, even
under the microscope.
And so if you used
the right light
and you looked very
carefully, you can often find,
as you can see on the
far right, I hope,
some very fine cracking
in the exterior.
But it's very complicated
with these objects
which have different
finishes on the surface.
And so sometimes you have
a high degree of polish
and a very nice surface,
and on the far left,
we show a highlighted
flute and we believe
that is a pristine
surface but in the middle
that is actually a rough
polished surface and you look
and you look is that
deteriorated, well,
you know, not so easy to tell.
And if it is just a
question of hydration
and Stephanie showed how we can
actually detect hydrated water
in the glass, you are never
going to see it with your eye.
So this early stage is
quite difficult to assess.
When you get to severe
cracking, however,
you can definitely see it,
especially under the microscope.
But when you can see it and when
they are foggy, unfortunately
that means that the
deterioration is very advanced
and it's difficult to
intervene at that point
to preserve your objects.
And I show here, three
images of flutes that we took
under the microscope, and
this is our friend 717
but that is obviously the
flute in very bad condition
that we focused on a
lot in our studies.
So beyond just earlier or
later types of degradation,
we also noted some other
conditions, and one is looking
for crystalline deposits which
in the literature have been said
to be an early sign
of deterioration.
So, therefore, we were really
kind of looking for them.
And we did find all kinds
of material on the interior
of the flutes and we
did take samples often
and we did Raman
spectroscopy on those samples.
And on your left,
you can see an image
with some different
material, looks crystalline,
we took some samples,
and unfortunately all
of those samples that
we have taken and looked
at with Raman spectroscopy
have turned
out to be what I would
call polishing debris.
We found iron oxides which are
likely from jeweler's screws
and we also found
calcium carbonate
which very well also could
be used as a polishing agent.
However, our samples
that we aged
in the environmental chamber
are a very good use here,
and on the right, we have a very
high magnified image looking
right in a crack of a quite
deteriorated model sample,
this is a replica glass,
and there does appear
to be material inside
the cracks.
And Stephanie was able to get
a very beautiful Raman spectrum
of that material and in fact it
has a very good identification
with potassium bicarbonate.
In that case we can say, yes,
there is a deterioration product
and may be that is something
that we can even find
or expect could happen.
And we also had x-ray
defraction done of these coupons
and what I have circled there
are peaks, so as you should know
or do know, glass is a
completely amorphous material,
so normally if you
did x-ray defraction,
you would just have that big
lumpy peak there but there
are some very sharp peaks
and that is indicating
that there is some
crystalline material,
and as the percent potassium
increased in the samples,
you see more of it and this
is something that is happening
with artificial aging and
not something to expect
in an early stage of
deterioration in these glasses.
Although we have not seen
it yet, it is something
that we possibly could find in
very deteriorated materials.
There is another condition that
is a very important condition
and we know from what is
known about glass leaching
and from our model samples
that we could expect
to develop an alkaline surface
on the flutes themselves,
and on occasion,
we have seen flutes
that do have visible
liquid alkaline drops
and this is often
called weeping.
Again we are trying to get
away from these type kind
of jargony terms since
not everybody uses
them consistently.
We only, out of our 19 flutes,
have only seen one flute
and only one of its joints that
has this condition, and I think,
you can see it pretty
well in the images
that I show there are these
teeny, tiny, dew-like droplets,
and we also on that same flute
see what appears to be a kind
of pitting which
could have occurred
from the droplets drying after
they had acted corrosively
on the surface but that can also
happen from water in cleaning.
So, we suspect-- and this did
not happen on our model samples
and we suspect this could
be another mechanism
that involves the
hydration of the glass
and then a sudden
change in humidity
that can cause this
phenomenon to occur.
And we are doing some new
experiments to verify that now.
And so if we put these
observations together
with our observations on the
model glass, we actually see
that the model studies are
supporting what we see quite
well, and just comparing
them kind of side by side,
it's very important that we have
the model studies support the
observation that the high leaded
glass flutes are quite stable
compared to the potash
glass flutes
because we only had
two here to look at.
So it would have been
very difficult to make
that conclusion, but now
that we have model studies,
I think we can say
that pretty safely.
We also saw right off the bat
that we had a very
high incidence
of deterioration among
the potash glass flutes.
And the model studies
are predicting
that the actual amount
of potassium
in the base glass is
itself a predictor
of the inherent instability
in the glass itself
and that is quite important.
We have seen little or
no crystalline deposits
on the flutes themselves,
which is not what is predicted
in the literature, and what the
model studies are telling us is
that that is something
that we should associate
with very late stage
deterioration and may
or may not occur
eventually in these objects.
And as I just said we can
have this other phenomenon
of liquid alkaline drops and
we have taken pH measurements
of the drops themselves
and they are like 10,
so they are extremely corrosive.
And all of this work
together really helps us
to understand what is
going on in the flutes
and really does justify all the
trouble and expense that we go
to and have gone to at the
library to design new storage
for the flutes and that is
because the environmental
factor is very important
and can't be ignored.
We are doing artificial
aging and we do think
that it is reflecting what goes
on in the flutes very well,
however, that was
at steady conditions
and very controlled conditions,
and of course these flutes have
had a life with different owners
and different museums and have
been exhibited a lot or not
or have been in a drawer
and they have been exposed
to different conditions and that
probably is the deciding factor
of the condition that
they are in given
that they have inherent
instability.
And we would like to point
out again with our flute 475,
which Stephanie showed before,
that in the four joints we
can actually see different
conditions and you can see that
in this beautiful photograph
by the fogginess in the
head joint, which is on top,
and then on the third one, which
would have been an extra joint
that was made for
a change in pitch
that was probably put away,
okay, we are theorizing,
but it is in a pristine
condition.
And these four joints were made
with roughly the
same formulation.
And so it is really
a beautiful example
of how the environment can
affect the condition including
the player's breath and so we
have often seen the head joints
to be in worse condition
and we think that is
because of the increased
exposure to moisture
from the breath of the flutist.
So, in summary, we do want
to point out for anyone
who has a flute and
looks at it themselves
that it can be very difficult
to assess the condition
just with the eye.
And we have come up
with some tools and many
of them are very simple, and
we are very proud of that
that can be used to supplement
what you see with your eye
that can really help assess
whether you have an unstable
material and what
condition it's in.
And of course, we
feel very strongly
that the interdisciplinary
aspect
of our research has
added tremendous value
to what we understand about
these flutes including
to what we understand
about Laurent himself,
who was not just an
innovator and a craftsman
but definitely a businessman
because the bottom line was
probably the cost of making
that flute [laughter]
and we believe
that is probably why he made
the potash glass substitutes.
And I just did want to conclude
with one more second here
about the fact that you
know we have been doing this
for four years-- this research--
and you know, I really--
I sat down and I said to
Carol Lynn what have we learnt
and I was so happy to hear that
as a curator, Carol Lynn feels
that she has gained so much
in terms of learning how
to ask questions
and to better think
about the material properties
of an individual object
when she is the caretaker,
and of course never
to assume because,
as we all know,
these flutes are still
listed in most catalogues
as crystal flutes,
so we now know
that the actual story
is quite different.
But the scientists, I think,
we all have learned
different things as well
and not just how rewarding it
is to participate in the care
of historical objects but
the importance of expanding
on our understanding of
something that you know a lot
of people would say, oh, we
know how glass deteriorates,
that is all completely
done already,
what are you spending your time
on that for, but every type
of object is different and
I think we have learnt a lot
about how these may
be deteriorating
in a slightly different way and
that we should also notice it,
so thank you, that's it.
[ Applause ]
>>Fenella France: And
without further ado,
our second speaker,
Jayme Kurland.
>> Jayme Kurland: Good
afternoon, I am very happy
to be here and I would
like to thank the Library
of Congress for the invitation.
I also must thank my
coauthors who I wish were here
because they did much of
the scientific research
on these objects but
I hope to be able
to share their work with you.
My name is Jayme Kurland,
I worked at the MFA
as a curatorial research
fellow in musical instruments
for the last four years.
When I began working
with the collection,
my first project was
working on a project related
to the auloi of Meroë.
I am happy to share the
progress my colleagues
and I have done on this project.
When we set out on this journey,
we did not know what to expect.
We hoped to learn more
about these instruments
and hopefully create replicas
but we have learnt so much more.
An aulos or the plural auloi
were the principal wind
instruments from antiquity,
also known to the Romans
as tibia or tibiae.
The instruments have double
reeds like modern oboes
and were played in tuned pairs
with one pipe primarily playing
a melodic line while the other
would play the drone.
Unlike a modern wind
instrument that uses both hands
on one pipe, aulos players
or auletes can only use one hand
per instrument limiting their
melodic options.
Early aulos finds are
made of wood or bone often
with metal reinforcement
over the joints
but construction
evolved over time.
By the Hellenistic and
Roman imperial periods,
mechanically sophisticated
systems were made
of various metals,
bone, and wood.
We see here the various
mechanisms
that we have seen
on the MFA's auloi.
The fragments have
either a bone or wood core
with two fitted bronze
sleeves surrounding the core.
The bronze sleeves
measure about 0.3
millimeters thick or less.
The top of the instrument
features a bone bulb,
which served as the reed insert,
and the flared bell
would be located
at the end of the instrument.
There are various types
of advanced mechanisms
including sliders,
rotating cuffs, and chimneys.
Unlike modern woodwind
keys that move up and down,
these sliders would slide
over the tone hole allowing a
larger pitch [inaudible] given
the limited size of
the player's hand.
The sliders could reach
notes out of reach.
The rotating cuffs could open or
close a given tone hole allowing
for minor changes
in modality or key.
Here we see some of the
fragments in further detail.
On the top left, we see a
cross-section of one fragment
which clearly shows the bone
core tinted bluish green
by the corroded metal with
two thin sleeves of bronze.
Next to it, we see a beautifully
cast dolphin holding a scallop
shell in its mouth.
This was on top of
a sliding mechanism.
Now that we have seen the
basic mechanisms and anatomy
of these instruments, I
would like to take a minute
to contextualize them
within Greek mythology.
When I began working
on this project,
one of my first tasks was
surveying the MFA's collection
of ancient art searching
for depictions of auloi.
I was thrilled to find that
the MFA holds over 100 examples
of iconography featuring
the instruments.
They are also in various media
including Etruscan painting,
Greek sculpture, carvings
on coins, and etchings
on gemstones, and of course
ancient Greek pottery.
This red figure ceramic bell
krater dating to about from 370
to 360 BC portrays the
origin story of the auloi.
The goddess, Athena, who is
said to have created the auloi,
is seen playing the
instrument under an olive tree.
While entertaining the Olympian
gods, she becomes embarrassed
when she discovers how
distorted her face appears
when blowing the
reeds of the auloi
and thus casts the
instruments aside.
Marsyas, a Phrygian satyr,
shown at the far right,
finds a discarded auloi, claims
them as his own invention
and becomes famous for
his beautiful playing.
Apollo, depicted to the right
of the tree, is challenged
by Marsyas to a godly
battle of the bands.
The terms of the
competition dictate
that the winner would choose
the punishment for the loser.
Both play their instruments
with great skill,
Marsyas on the auloi and
Apollo on his stringed lyre.
Apollo challenges Marsyas to
play his instrument upside down,
while this was down easily on
the lyre, Marsyas was unable
to play his auloi
in this fashion.
Serving his judges, the muses
awarded the contest to Apollo.
As punishment, Apollo
had Marsyas hanged
from a tree and flayed.
The pipes of his auloi
reportedly joined
to his eviscerated body to
create the first bagpipe.
[ Laughter ]
Auloi are well documented in
Greek mythology, iconography,
and event texts including
the Bible, played by both men
and women, they were
used for celebrations
such Dionysian festivals
but also for funerary rites,
which may explain why the
MFA's auloi were discovered
at a burial site.
The instruments were often
played alone meaning one player
playing the two instruments,
not one pipe at the same time,
but were also used to
accompany singing and dancing.
The numerous artwork showing
auloi performers not only
illuminate various
classical myths
but also provide useful
information regarding how the
instruments were played
and what their role was
in the ancient world.
Due to the physical challenges
of playing two instruments
at once, a phorbeiá or halter
or mouth strap was used as seen
in this image to help the player
keep the two instruments in his
or her mouth but also
helping support the
player's [inaudible].
While we know these
instruments were double reeds,
but due to the reeds
organic materials,
we have very few
remains of them,
which were mostly likely
made of Arundo donax,
a common species of cane.
Scholars have been using
these native materials
to ascertain how reeds were made
and thankfully there are
some iconographic examples
to show roughly the
shape and size,
although they aren't completely
accurate in many cases.
At the top, the photo is
of reeds made by scholars
at a workshop I went to
in Italy where we tried
to make these reeds out of
the traditional materials
but also trying to figure out
how they were made historically.
As I mentioned before, early
aulos finds are made of bone
or wood and they didn't
necessarily have many
mechanisms, if any,
but by the Hellenistic
and Roman Imperial periods
mechanically sophisticated
systems were made of various
metals, bone, and wood.
We see here some extant
examples of the later,
the more technologically
advanced instruments.
To understand our
fragments, let's go back
to when they were found.
In 1921, a Harvard
University Museum
of Fine Arts expedition led
by George Andrew Reisner,
the MFA's curator of Egyptian
art and a Harvard professor
of Egyptology excavated
the burial site
of a Nubian queen Amanishakheto
of Meroë in what is now Sudan.
Amanishakheto, who
reigned between 10
and 1 BC was a powerful ruler,
and after a period of conflict
between Meroë and the Roman
Empire, she signed a treaty
with the Emperor Augustus that
set the stage for a new era
of trade and communication
between the two powers.
Kingdom of Meroë was
a metropolitan center
for trade along the Nile River
Valley and near the Red Sea
which saw cultural exchange with
people from the Mediterranean
and Western and Central Asia.
Other artifacts found in the
area show an advanced level
of metropolitan quality
and sophistication.
Here we see a drawing from
the early 19th century
of Queen Amanishakheto's
pyramid, and at this point,
it was very well preserved,
only with the top part
just a little damaged.
This burial site
outside the city
of Meroë had already been
discovered by physician
and explorer Guiseppe
Ferlini in the 1830s.
While investigating the pyramid,
he came upon a treasure
trove of gold.
Unfortunately, during
his exploration,
he and his team raided and
destroyed many structures
on the site and took
dozens of pieces
of gold and silver jewelry.
Fortunately for us a
few objects remained.
There is another photo
of the burial site
after Ferlini had visited it.
So in 1921, on his
expedition, George Reisner
and his team unearthed
the entrance
to Amanishakheto's burial
chamber at the entrance
of her tomb and found a large
cash of ancient auloi buried
in the dirt, at least 12
instruments, thus six pairs.
Thankfully, Reisner was
one of the first to take
in situ photography during
excavations and we have a photo
of these instruments
before they were excavated.
Unfortunately, they seem to
be have been excavated bit
by bit instead of
in a whole block,
thus by the time the
excavation was finished,
most of the pipes
were in fragments.
But this grouping of
instruments is one
of the largest cashes
ever excavated.
These fragments which
we see here were kept
in original excavation boxes
until our project began in 2013.
We also know of other auloi
found nearby in the city
of Meroë although the example
on one side is an assemblage
of fragments that were at the
University of Liverpool Museum,
although we have not
been able to find them,
and on the other side, we
have a statue of an aulete
or an auloi player found
in Meroë as well.
After the instruments were
excavated, they were shipped
to the MFA in 12 original
excavation boxes with fragments
of various sizes and shapes in
various stages of degradation.
Some boxes were lined
with muslin and many
of these had original
field notes
in Arabic from the excavators.
Over the years, a few scholars
came to study these fragments.
In 1946, Nicholas
Bodley, known to many
as Nicholas Basarabov
[assumed spelling],
wrote a very preliminary
report on the fragments.
And in the early 90s, English
researcher Maurice Burns came
to study the instruments having
examined many other auloi
in collections worldwide.
In 2012, Olga Zukowska
[assumed spelling] came
and examined the
fragments and urged us
to consider an in-depth
project focused on them.
So in 2013, after
receiving generous support
from museum donors, the
Musical Instrument Department,
the Department Of Art
In The Ancient World,
and the Museums Conservation
Department joined together
to focus our efforts on
the auloi of Meroë.
Susan Gonsika [assumed
spelling] our conservator,
triaged the objects and decided
that we must first
re-house the instruments
and take high resolution
photography.
So she created custom
archival acid free boxes
and rehoused the fragments.
Although the MFA's fragments
had languished in their boxes
for almost a century, we
were actually quite lucky
that earlier irreversible
attempts had not been made
to conserve them.
Like several like instruments
and other collections
were put together long ago
with irreversible
waxes and resins.
Our fragments, although severely
corroded, were untouched.
So when Susan was able to see
the fragments on a clean surface
in the new boxes, she began to
see fragments that were begging
to be joined together and used
a reversible adhesive solution
to adhere the pieces.
She then took the fragments
to the MFA's conservation
scientists
to perform various tests
we see here x-ray images
of several of the fragments.
One outstanding mystery was
knowing how the cylindrical
bronze sleeves were
fabricated and the x-ray shows
that there were no solder seams.
We think that the seamless
tubes were cast from tin bronze
and then likely further
hammered,
possibly around the metal core.
Final turning and smoothing
of the surface with the lathe
like instrument facilitated
the perfect fitting
of the extremely
thin straight tubes.
As we see distinctive parallel
markings on the metal surface
that have not been
mineralized by corrosion.
There were also several
pieces with mysterious
but seemingly purposeful cuts
in the metal, as we see it
on the bottom part
of this slide.
As we saw briefly earlier,
this specific scan showed us
that there were rotating sleeves
adorned with knobs that gave --
allowed a given tone hole
to be opened or closed.
So they would be turned,
you can't really see it
but the sleeve would
turn over the tone hole.
Some of the fragments had
wood cores instead of bone.
The British Museum's
Carolyn Cartwright,
an ancient wood specialist,
was able to identify our sample
as Olea europaea,
European olive tree wood.
And the radiocarbon
date is between 52 B.C.
and 54 A.D. Metallography
showed redeposited copper
in some of the tubes.
And a brown sleeve on
the bone bulb piece
at right was actually
corroded silver.
Conservation scientists Michelle
Derrick and Richard Newman
from the MFA conducted
scanning electron microscopy,
an energy dispersive
x-ray fluorescence.
Which gave us a much better
data on the chemical composition
of the various metals
used in the fragments.
Thanks to quantitative elemental
analysis on the cross sections
of the tubing, we learned
that the tubes were made
of tin bronze with about
90% copper and 10% tin.
We also took some fragments
to Massachusetts General
Hospital to be CT scanned.
Although the -- due to
the high concentrate --
concentration of metal
we did not see much
in the resulting images.
Scanning electron microscopy
imaging also showed fibrous
materials in one of the holes
of the knobs of a sleeve neck
of one of the rotating
sleeve mechanisms.
MFA textile conservator Joel
Thompson identified this
as flax fiber.
Now as to the purpose of this
there isn't a firm consensus.
Some think that the fibers would
have served a decorative purpose
hanging down from the instrument
while others think they might
have been used to move the
sliding mechanism that was
out of reach by pulling
the thread.
So as Susan began to read
and hear more fragments,
some startling identifications
were made thanks
to institute photography.
Susan created this image
which shows a convincing match
of the fragments in
their current state
to the excavation photo.
As the fragments became longer
with more joins we needed
a better storage solution,
thus we created this
channeled row configuration
out of archival ethyl foam,
which allowed longer
joins to be made.
I should mention that we are
not re-adhering every fragment
so this arrangement allows
us to show potential matches
that are either not
stable enough to mend due
to material loss but
also allows us to try
out various configurations .
In 2015 we invited ancient
alloy specialist Stefan Hoggle
from the Austrian Academy of
Arts and Sciences, Olga Zukowska
from the European Music
Archaeology Project, EMAP,
along with instrument
maker and engineer
from Middlesex University,
Peter Holmes to come
and examine the fragments.
You see us in the ancient
world library looking at all
of the boxes of the bits.
Stefan created schematics which
plotted different ancient modes
or scales and where the
associated tone holes would be.
By first lying out the
longer like fragments,
ones with similar measurements
and materials side by side,
he started to be able to
see musical connections.
So this is a map of one
of his schematics showing
the different placement
of where tone holes should be.
And because of this kind
of schematic he was able
to also identify where certain
mechanisms would have been
placed due to the ergonomics
of playing the instrument.
He then took the data
and modeled the scales
using software --
a software program he designed.
His schematics showed
approximate location
of the holes in relation
to the ancient modalities.
This allowed him to associate
fragments with missing joins
and arrangements that
made musical sense.
Especially in fragments in which
there weren't any very clear
joins that could be made,
he was able to estimate what
fragments would fit where.
Using this technology
he was able
to better determine the match
pairs of the instruments
since they would
be in the same mode
and would be roughly
the same size.
So this is what we came to.
Stefan, Susan, Olga, and Peter
were able to find like pairs
and rest them in what we think
are their proper orientation.
The long pipes at the bottom
are the longest ever found
and we have determined that the
dolphin sliders would have fit
on them, allowing sound
holes out of reach
to be covered and uncovered.
So now I'd like to
play a brief video.
I'm not able to get
to the screen.
Sorry.
Yeah.
So these are instruments
that were 3D printed
that are very like
our fragments.
[Music]
So given all of the
information that we've gleaned
and now having a basic
type of replica made,
we hope that Peter Holmes and
Stefan Hoggle will be able
to create replicas
of our instruments using
the traditional materials.
So here's a photo of what one
type of instrument might look
like using traditional
materials.
As I come to the end of
my presentation I would
like to highlight how
wonderful the cross departmental
collaboration was for us.
I think that all departments,
this was a very unique project
for the MSA and I don't
think to this date
so many departments have been
involved in a single project.
But to have everyone
come together
and really help us
learn more about one
of the most important
instruments
in our collection
was really amazing.
And it really helped
to have perspectives
in art history conservation
science and music.
So we hope to tell this story in
a small exhibition or some sort
of digital exhibition
in the coming years.
And with that I'd just like
to say that we continue
to update our conservation
project page so continue
to follow our project
there and I look forward
to answering any
questions at the end.
Thank you.
>> Fenella France: And
a third presentation,
Jean-Philippe Echard, who I
know had significant problems
and challenges trying
to shrink 15 classes
of research into this.
We very much look forward to it.
>> Jean-Philippe Echard:
Thank you, France.
Thank you, France,
for the introduction.
Thank you Carol Lynn and
Lynn for the invitation
to this talk series lecture.
And thank you to the
Library of Congress.
We -- I'm from France
so pardon my English
if it's not totally perfect.
I work in the city [inaudible].
Which is in the public
institution dedicated to music
in France, in Paris
in the Northeast 1977.
This institution has three
main feet, if I may say.
Dedicated to concerts,
dedicated to education in music
to a wide range of audiences.
Kids to adults.
And also heritage about music.
It's located very close to
the Conservatoire de Paris
which has been founded in the,
during the French Revolution.
I show here one of
the concert halls.
It's the largest
concert halls we have
in the institution
in the [inaudible].
It's La Salle Pierre Boulez
and we have also two other
smaller concert halls.
Here are few views of the
gallery of the [inaudible].
So we exhibit instruments but
also fine arts, collection,
paintings, sculptures dedicated
to music and presenting music.
So it's not only a collection
of musical instruments but also
of art works dedicated to music.
We have approximately 1,000
pieces on view and for a total
of 7,000, roughly
speaking accession numbers
in the collection.
It is the French
national collection
of musical instruments on
music related artworks.
And so it's quite unique
at least in France,
It's a collection -- I mean,
for musical instruments it's
a collection that is owned
by the French nation,
the French people.
It was created around the French
Revolution without the origin
of the collection and it
has been growing since.
Today we have, I show
here a few numbers.
We -- one thing I could point
out is we are playing instrument
of the collection that are
played only in the building.
We have a dedicated
auditorium which you will see
at the end of my talk.
250 seats approximately
dedicated to chamber musics
for instance and
we play instruments
of the collection there in
a programming, which is part
of the large program of concerts
of the whole [inaudible].
So it's, roughly speaking,
15 concerts a year plus every
two Sunday in the afternoon.
If you buy your museum ticket
and you come visit the museum
there are what is called the
[inaudible] with a more informal
way of presenting music concerts
in the galleries of the museum.
We also receive specific
visitors which are scholars,
or musicologist, or
musicians, or instruments maker
and they come to the
lab, conservation lab
and they are studying
in death this instrument
or that instrument to make a
copy to get inspiration of how
to study for academic research.
Which you see here,
a group of a school
from a violin making
school in Germany.
We in the staff of the
[inaudible], there is a group,
small department,
dedicated to research.
So we have a conservation lab,
research, and conservation lab.
And we are we are also
[inaudible] and an assistant.
And part of our work
is to perform research.
And so our research article
activities are educated
to several fields and
sometimes they interconnects.
So this is music history in
general but mostly the history
of the makers, the musician
and the collectors related
to their musical instruments.
The history of techniques
of musical instrument making
as part also of the
cultural history.
So we study, of course, the
materials and the technique
of elaboration of the
instruments but also
in their technical
cultural context.
And sometime it leads to
economics studies or such kind
of studies which seems
kind of far related
to the music instrument
making itself.
We also study, in some cases,
the way the musical
instrument works.
How it sounds.
So these are more
the fields of physics
and acoustics in particular.
We study also conservation
like the treatments
that should be specifically
developed for instruments,
especially when instruments
are kept in playing conditions.
And finally, we think and we
work on the heritage values
of the musical instruments
which are part
of our cultural heritage.
It is different to keep and to
preserve musical instruments
in a national collection like we
do than to conserve instruments
in your own private
collection when you are musician
and collecting instruments.
So it's, these are
not the same things.
And the values that the
society of the owner
of the instrument attached sees
in the object is not the same
and we try to consider
this aspect also.
I forgot to mention, sorry.
That we are as, a team, part
of a larger [inaudible].
We are part of the CRC which
is a French Public Research Lab
of the CNRS agency.
And CRC is a very important
laboratory for the studio
of 19 year olds but also
conservation in general.
And we are part also
of a several consortium
which allows collaborative
research in terms of history
of music history but also
other experimental sciences.
And we you see the logos here.
So now we can go a little
more in depth and focus
on the Stradivari violins
in the Paris collection.
I'm now the curator in charge
of both stringed instruments.
So these five violins are --
I'm in charge of among
other instruments.
And this are very --
this is a nice group.
You have a nice group
of Stradivari insurance
here as well.
And it's good these instruments
are in public collections.
They have been given
by bequest mostly
to the Paris Conservatoire
Museum in the late 19th century
and in the early 20th century.
We count -- we are lucky
to count five instruments
that enter.
So before 1935 in
the Paris collection.
We count also other
items by this workshop
by Antonio Stradivari.
And this are one
guitar, one of the six
or seven remaining
details named [inaudible].
We have also [inaudible]
a very marrow viola named
the [inaudible].
And we have also six
molds for [inaudible]
and smaller instruments
coming from the workshop
and values fingerboard
and pieces of instruments
of [inaudible] like
original fingerboard.
And such tiny instrument
with which are very important
for the research and
the original state
of these instruments.
So among these five Stradivari
violins i will go more
into detail to talk about the
[inaudible] which is name --
which is from the year 1708.
Before that, I am like
France say earlier,
there were various researches on
the violins at the [inaudible]
so namely researches
on varnishes
and it was actually my
PhD a few years ago.
And also the identification
of techniques and ingredients
that were used to varnish
Stradivari violins but also
in the technical context
of European vanishing
of musical instruments.
So I studied with a team.
I studied lutes from the
17th century, the varnish.
Other violins from other
centers of making in Europe
and to compare all this
in a quite series approach
or cut copies oriented approach.
Since 2010 and the end of my
PhD I -- research went on again.
And I would like to mention
the work of [inaudible]
who was my PhD student later
and she worked on a specific,
very specific work
which is of interest,
especially to violin
makers nowadays
who prepare their own varnish
according to historical recipes.
We studied the parameters of
like the oil to resin ratio
because in the chemical
analysis I had performed,
you couldn't see,
detect properly the
ratio of the ingredients.
So she worked on that.
Studying this parameter
and also the cooking time
and the cooking duration
to prepare the varnish
and how it would connect
to the coating properties,
layering properties,
color properties,
etc. And she was allowed, she
was able to present like a range
of parameters which --
in which it's possible
to make a good working varnish
with only two ingredients,
which is drying oil
and fine resins.
Other -- there are
other topics than vanish
when we speak about violins.
And I may mention ongoing
works in the past few years.
Two works are on wood.
So identification of
woods and dating of woods.
And we have been
recently working,
namely on the purfling woods,
which are tiny bits of wood
in the board and in the back
of the instruments to try
to identify the wood species.
And it's not that easy when
you know the typical scale
of wood structure compared to
the width, very narrow width
of the strips of the purflings.
Another aspect, which is
not experimental science
but more history research, is
the research on [inaudible]
and I'm mentioning
here two works.
We have been lucky in 1909
to receive the bequeath
of the [inaudible]
1716 Stradi violins.
Among six instrument
and eight bows coming
from the Coveney family and I've
been working on this bequeath
to -- on this group
of instruments
to find the provenance and
to discover previous honor.
And we were able to go back
through the early 19th century
for this group of instruments,
which is not the total history
of the instruments but still
it's a good step learning,
going back in the past.
I'm also mentioning
an upcoming monograph
on the [inaudible] violins.
So it's a 1724 Strad which was
bequest by [inaudible] to the
to the museum in 1909 again.
And a little book monograph
will be published and available
for the moment in French only
but I'm sure you will read
French on this violin.
So now the 1708 davydov violin.
This instrument is from a
conservation state point
of view, in a very good
general conditions.
There were no open cracks.
No woodworm galleries
that were inside.
So we performed institute
imaging techniques
such as x-ray, radiograph,
and [inaudible] examination
to check this.
And it was in very
good general condition.
We were then able to
consider to bring it back
to playing condition because
this instrument had not played
for at least thirty to forty
years in the collection.
It has been kept
either in storage
or behind the glass case only
and we were considering to,
if there was a possibility,
to play at least one
of these five violence.
And the davydov seemed
the most suited for this.
1708, it's considered to be
in the most esteemed period
of Stradivari instrument.
Some of them -- some
people named this period the
golden period.
But whatever it means, it
was a representative object
with all the main part original.
So the whole sound box as
well as the scroll coming
from Antonio Stradivari work.
And it was still a challenge
to bring it back to
playing condition.
It has not been played
for thirty to forty years.
We do not have restoration --
a violin restorer in the staff,
which would do the work.
So we would have to contract the
work to a private conservator.
So the challenge was
to bring the workshop
of the conservator
inside our science lab.
And it was already some -- there
was some thought given to that.
And also, what should we do?
What should we give
the people to hear
and to see during this process?
And it was the general approach.
And we -- it took some time to
do it, to do this and I'm going
to lead you to this little
journey and which will go
to the use of science
objects as well.
So the -- a few words
on the provenance
of the davydov is not called
davydov the cellist who --
and one of the cello
of Stradivari is named
davydov after Karl Davydov.
Davydov was and is a
common name in Russia.
And this davydov is Vladimir
Alexandrovich Davydov
and is not apparently
related, not apparent,
to the Karl Davydov the cellist.
It's another one.
And I'm pointing
this because in books
that are gathering the
history of many Strads,
you often find the
confusion between the two.
In especially, for
our 1708 violin.
Vladimir Alexandrovich
Davydov, his mother was French.
She escaped when she was two
from Versailles during
the French Revolution.
And this woman, she
eventually married a general
of the Russian army
when she was older.
And Vladimir Alexandrovich
Davydov was their son
but he was still very
attached to France.
And in the end of at the end of
his life he was being a diplomat
or a special consular
for the Tsar.
And he was often to France
for political reasons
or diplomatic reasons.
And we know that at least
in 1880 he was already
owning this violin
because the famous violin expert
and dealer named [inaudible]
who was very active
in in Paris in 1880.
Saw this instrument and
described it at the back of one
of his own business card.
So you see the photograph of
the back of the business card
of [inaudible] and
this is now conserved
in the archives national in
France where he described,
even the state of conservation
there is a little bit
of a songbird post patch,
etc. Very [inaudible] so,
nice looking red varnish, bright
red varnish, well preserved,
etc. And then so one year
before his death, Davydov went
to see the head of the
Conservatoire at the time
in Paris and told him, I will
give you by big quest my Strad.
And he died, he passed
away one year after.
And in 1887, the Museum of
the Conservatoire received
for the first time
one Stradivari violin.
So it was a big thing in France.
It was in the newspapers,
etc. And the condition
of the bequest was, this
instrument shall be played
by the first violin
prize each year,
you know, at the Conservatoire.
The person awarded the first
prize violin could play this
Strad for the concert after
the graduation ceremony.
[Inaudible].
And the first one who played
it in 1887 was Fritz Kreisler
and he was 12 or 13 at the time.
And so Fritz Kreisler
played it one night only
for very tiny piece.
So this is anecdotal but
I wanted to share that.
The violin was later exhibited
for the 200th anniversary
of the death of Stradivari
at the exhibition
in Cremona in 1937.
And after, it was lent
to several students
for international competition.
And including [inaudible]
in '81 and apparently,
according to the records,
it was the last loan
to a young musician.
And after that the instrument
was not exactly maintaining
playing condition and it was
just briefly played and tried
by [inaudible], who is one
of the Paris Conservatoire
violin teacher
and also a musician, obviously,
very briefly in 2004 and 2007.
But the setup of the
instrument was not perfect.
The fingerboard was not
flat properly adjusted,
the bridge as well had some
issue, etc. So there were issues
in the setup at least.
So we thought if we were to
play it again we should play it
in a good setup state for
musicians to be comfortable with
but still, according
to the [inaudible]
and the noninvasiveness on
original part, etc. So we were
to consider the heritage
values associated not only
to the violin in general
but to each of it's parts.
So even the fingerboard
if you think of that,
the fingerboard dated
circa the 60's, 1960's,
the current fingerboard
on the violin.
And it was a work of
[inaudible] who was a prominent,
maybe the best known are
the most famous violin maker
and expert in the 20th century.
So it's also part
of the heritage
and should we keep,
it not keep it?
So we decided to make 3d
laser scans measurement
of the original, of the
before restoration state,
before removing this part,
the setup of [inaudible]
and keep it aside.
So now it's kept in
the storage room.
The 1960's set up
and put a new one
because the previous one
was not able to play.
This illustrates the fact that
a violin is a composite object
which has evolved
in the centuries.
So it's not -- even if this
violin dates 1708 on the label,
even if its original part
are all from 1708 coming
from Stradivari, still the setup
or the sun post or the pegs
on the tail piece
are not original.
But they are still part of the
material history of the object.
And this were the
main concerns we had
in the restoration process.
So documentation of the
state before restoration,
before treatment
was very important.
Also we wanted to improve the
visual aspect of the instrument
because the instrument
was really dirty
and we will go on that.
The appearance was
not very proper
for the good correct usability
of the wood of the vanishes,
etc., especially
on the soundboard.
We decided in the course
of this treatment to try
to use scientific
imaging technique
or measurement techniques
to follow the process
of the restoration,
so to properly document the
initial state before restoration
and document the evolution
of the instrument
during the treatment.
So this will be the
focus of my talk now.
I'll give you here a few images
of some aspects of the treatment
and the restoration process.
I want to mention the very
good collaboration we have had
with the violin conservator
with name Balthazar [inaudible]
and he has his workshop
named [inaudible] in Paris.
He is the one who did
the conservation work.
And you see part of him, these
are his hands and gloves.
You see here he is re-gluing a
little crack on the soundboard.
And so a few views of
some aspects of the work.
Here we are on the scroll and
you may see that the original --
these are the original holes for
the pegs so they have not been
on this one bushed
and re-drilled
which is frequently the case.
So we are lucky to have
this original holes
for the peg holes.
So they were reinforced
by spiral bushings here.
So it's during the operation,
afterwards of obviously it
has been finished properly.
You see the finished stage
in the middle under UV.
And Balthazar also treated a
little crack here on this side,
which was worrisome
if we were to think
about the playing condition
and the regular tuning
of the instrument.
And it was very finely filled
with a piece of adjusted piece
of wood and it's
really fine now.
In his expert look
at the surfaces
of the instrument led Balthazar
to present a kind of a map
of the various layers
of materials
that were on the soundboard.
And so everything is -- we have
for reference a UV light image
which is very frequent to
document the surface state
of varnished instrument.
And we were really worried
about this layer in this area.
Very heavy, very rigid material.
A little bit like concrete.
A very thin layer of
mineral like material
and not very adequate
red black patina
which had some original
varnish under.
So this were the main layers of
non-original materia we decided
to to remove or to make
it lighter in order
to improve the readability
of the underneath surface.
So you see in the -- these are
two pictures there on the left.
It's the original state
before any treatment.
And this is during
the treatment.
It's -- the treatment
is not finished
so it's -- now it's better.
It's more homogeneous even.
It's during the treatment.
But a lot of the patina on the
dirt, especially on the side
of the fingerboard area
and in this central part
of the soundboard were very
carefully, partially removed
or almost totally removed.
To track may be more objectively
the changes that occurred,
we used system, a
multispectral imaging system
that we've made built
in our lab.
And it's a way to collect the
light reflected by the violin,
using a system which is better
than a simple red, green,
blue camera with three channels.
We used a 14 channel color
camera, if you want to say.
And this allows -- so you
see here this the 14 bandpass
of the 14 filters and we collect
a series, a stack of 14 images,
each of them corresponding
to a very narrow band
in the visible regions
of the spectrum.
And this process allows to
measure the reflected light,
properly emitted
reflected by the object.
It's not exactly a
color measurement.
It's a measurement
of the reflectance.
It's related but
it's not the same.
And we did some comparison
in one of the band.
So we picked this band in the
yellow area, in the yellow area
of the visible spectrum
just to show it to you.
But we could have
picked the other bands
like in the spectral region.
The idea is, was
to subtract the --
to make a subtraction
like between what is now
the instruments looking
like minus what was the
instrument looking like before,
using this multispectral
reflectance imaging.
And it allows -- so
there is a false color --
so there is a quite heavy
foil for me at least.
My colleagues are very expert
on that data processing
data correction,
so that you can subtract.
And you see the fourth color,
the pink area, shows to you
where there is more reflected
light emitted after a treatment
than before treatment
in the yellow region.
And it's a way to very
properly document and map
where material has been removed.
Where color -- sorry.
I said color and its color
scientists will not be happy
if I say that.
Where more light is reflected
from the instrument
in the yellow region.
So basically where
it was very dark,
now it's brighter in the yellow.
I'm showing only the
yellow but we can do
that for all the spectrum.
And you see there was
obviously a gain in brightness
in the central region but
also, I don't know if you see
that on the screen, but
this little badly restored
in the past, maybe in
the 19th century crack,
was a colored retouch that was
not well and we make it lighter.
So now it's a brighter area.
And dirt in this area
has been cleaned and here
in this corner it has
been cleaned as well.
So it's very precise.
Each pixel corresponds
to an area smaller
than one millimeter
on the object.
So it's quite finely restored.
Another tool we use
is more for geometry.
The variations in
geometry of the soundbox
and of the instruments
during the process.
So this is not a CT scan,
which is using x-rays,
it is a laser scan.
So it gets you -- you obtain
only the outer surface
of the object and
not the inside.
But still, it's an arm that
you can bring to the museum
and you don't have to move
the instrument to the CT scan.
So it's very easy and
there's a very good resolution
and you get directly on the
computer why you acquire --
you swipe the laser
line on the object
and you collect a 3D surface.
Then, like in the
multispectral imaging,
you can make substraction like
before and after comparison.
So this image is a subtraction
image of what is the difference
between when you -- when the
sound post is in position
and when the sound
post is not in position
because at some point we
removed the old song post
in the instrument.
And you see that when
you remove -- sorry.
When you place the sound post,
the area of the soundboard
is getting higher obviously.
It's kind of obvious for
violin makers who are here.
But there are movements
of the soundboard.
And you see this, usually
the soundboard is here,
touching here, the soundboard.
But the consequences
and the evolution
of the hate also
come up to here.
You see it's bluer here.
And it means that the
whole structure is moving
in a complex way.
So in the idea of the
risk assessment we take
when we make a modification
of the instrument
when we setup even a song post,
this kind of tools
could be very useful.
On a -- at a larger scale,
when we make this substraction
after treatment minus
before treatment,
we see a general
modification of the violins
where when you string the --
when you tune the instrument
when it's strung, obviously
the soundboards go lower
because of the pressure
of the bridge.
And it's -- what is the scale?
It's about one millimeter
lower deflection of this area,
which is not -- it's
a lot when you think
that the soundboard is two
and a half millimeter thick.
And interestingly also we see
that come relatively in terms
of relative position, the scroll
I mean, [inaudible] is going
up when you pull the strings.
And this kind of
modifications help also
and it gives you a
range of the scale
and the magnitude
of these changes.
And it's like the movement --
or relative movement of the
scroll is one millimeter also,
approximately in
the other direction.
So the soundboard is
going one millimeter down,
roughly speaking, and the scroll
is going one millimeter up.
So if you want to treat and we
are planning to use this kind
of 3D methodological tools to
follow, to monitor instrument
that are kept in condition.
It might be a way to follow
and to detect early enough
if the structure
is moving too much.
It's changing too much.
Third, I'm showing you another
technique, quite experimental
that has been developed by
our colleagues in [inaudible]
which is in Paris University.
And this tool is part
of the acoustics field
and the vibrations field.
You imagine you see
on the top a side view
of an array of microphones.
These are 128 microphone in
an array, in a grid matrix.
And they record sound
all at the same time.
They are synchronized.
So you collect on 128
channels simultaneously.
The acoustic answer
and the microphone.
So we don't play
the violin here.
We will not bow on
the instrument.
It's a tool to again look at
the way the soundboard vibrates
and how the instrument vibrates.
The experiment, you need to make
a little impact with a triggered
by computer -- a hammer
triggered by computer.
So you know where --
when it's triggered
and you synchronize
the sound collection
of the 128 microscope.
And this is giving you what
is called the near field
acoustic holography.
So it's giving you data
of the air pressure
modification of the mics.
But it tells you how
the soundboard vibrates.
And if there is a crack in
the soundboard, you will see
in the answer of the
machine of the technique.
So this is a very important
mechanical monitoring tool.
And here I'm showing
the radiated pressure,
some pressure.
It's an average on
the 128 microphones.
And the x-axis is the frequency
in hertz and you have modes
of vibration of the
soundboard which are appearing
as peaks in the spectrum.
I'm not a specialist
of this field
with my colleagues [inaudible]
our colleagues at [inaudible]
who are the experts on that.
But we evidence quite important
and noticeable differences
in the vibration mode between
the before the treatment
and after the treatment.
So this is currently
investigated
to attribute properly the
changes to this operation
in the treatment of that
operation in the treatment.
It could be the re-gluing of
the strengthening of the gluing
of the soundboard in
one part on the ribs.
It could be something else.
It could be the song
post position,
etc. It's under investigation
but I wanted to share that tool
with you which is
totally non-invasive.
The hammer is very, very
light and tiny hammer and just
to allow the soundbox
to vibrate.
So we comes towards
the end of my talk.
I hope I'm not too, too long.
And these three techniques
use light.
The reflectance in the
visible spectrum use a laser
to measure geometrical
modification and use vibration
in air, so sound, sound waves,
to analyze and to monitor
without contact the
changes on one instrument.
And it's to us we are quite
satisfied by these tools.
We have been experimenting
during this conservation process
and we hope to improve
and go on with the use
of this non-invasive tool, I
repeat, to follow the treatment.
So hopefully, finally the
instrument has been restored
and is in playing condition.
So what what should
we do with that?
I need to try to
show this to you.
Up. A little bit.
So this a recording that has
been performed by [inaudible]
in the auditorium
of the [inaudible]
[ Music ]
This instrument is now
in playing condition.
We are very happy with that.
The visitors and the audience
is very pleased with that.
And now we hope and we
are currently thinking
of further programs
with this instruments.
And it can be CD's, CD
recordings performed
at the [inaudible] and
also concerts programming
in the same venue, same hole.
So we are now considering
which project will occur
after this short
video you may find
on the YouTube channel
of the [inaudible].
I am -- I would like to
thanks a lot of colleagues
and the colleagues
in the science
in the research team
of the [inaudible].
So [inaudible], she is the
head of the lab and also
for the video production
[inaudible].
And outside of the
team of the [inaudible]
but it's showing the
interdisciplinary collaborations
we have with other scientists
Belthazor [inaudible] I
mentioned was the
conservator on this violin.
[Inaudible] who did the --
perform the reflectance
multispectral imaging with me
and treated the data
on multispectral
imaging with [inaudible].
[Inaudible] and Francois Olivier
for the near field
acoustic holography.
[Inaudible] from the
company [inaudible]
for the 3D laser scans
and Christian [inaudible]
for the wood purfling analysis.
And I thank you for
your attention.
Thank you.
>> Fenella France: [Inaudible].
So we will now take
questions from the audience
for any of the speakers.
We have around 50 people online
listening in so we will ask --
I will try and interpret the
question and we'll repeat
that so that our
off-site audience can hear
their question.
And answer and we
will also check to see
if there's any questions
from outside as well.
So the floor belongs to you all.
I open up.
But I must admit, it's hard to
think after that last video.
>> Unidentified Speaker: I have
a question for Jean-Philippe.
Was there any documentation --
you have very well described
how you document what you did
from the moment you started
to do a preservation,
restoration of the instrument.
Is there a lot of record
of, on what was happening
to the instrument from the
time it was produced originally
until you started to work on it?
So you can see if what
you do is restoring it
to its original acoustic.
>> Fenella France:
So the question was,
was the documentation
prior to the treatment
and conservation work
that helps understand more
about what had happened
to the instrument.
>> Jean-Philippe Echard:
We have no record archives
of previous treatments
on the instruments.
Especially -- the
only documents --
the only document is
the instrument itself.
So unfortunately, no document
was kept for the modifications.
In some other instances we --
since we keep also
archives in our collection
from the workshop
funded by Loophole,
a very important workshop in
the 19th century in Paris.
We can't find -- we can find
such records but in the case
of the davydov known under
mentioning the scroll, the head,
the peg box, we have been
able to evidence that they are
onto some -- I don't
know in English
but the neck has been
changed three times.
You know, the neck is
usually not original
on violins of this period.
And we have seen two different
traces of changing neck work
in the -- when you look at
the peg box from the front.
So this is an indication
of the things that happen
of the material history
of the works
of previous repair
orchestra of the instrument.
But for -- so the second
half of your question was,
did we bring back the instrument
to the original state.
If I'm not wrong
>> Unidentified Speaker: Yeah.
I wrote it on the card.
It says, at the moment this
instrument has [inaudible].
It said [inaudible].
>> Jean-Philippe
Echard: [Inaudible].
In 1880 [inaudible] reports
that there is a repair
in the sound post area.
So it's a way to
date such a repair.
So since [inaudible] saw it this
repair was there before 1880.
This kind of relative dating
we have to deal with a lot
because it's very rare
we have archives records
of all the treatments.
>> Unidentified Speaker: I
think that's [inaudible].
The acoustic -- sorry.
The acoustic technique
was very cool.
And you got, you know,
you got a spectrum
that showed a difference that --
are you subjectively
interpreting what you want it
to sound like, or what's
better or worse there?
I mean, how do you --
>> Fenella France: So the
question was the interpretation
of the acoustical analysis.
>> Jean-Philippe
Echard: And thank.
And this tool is
using sound waves.
The sound records -- so sound is
a variation of pressure of air
at microphone or at the ear.
And it uses acoustic or sounds.
But the aim of it is
not to record the sound
or to tune -- to
adjust the sound.
It is to monitor or record
the mechanical behavior.
So the way the plate vibrates
and it's by breaking modes.
So it's mostly vibration
if I'm correct.
I'm not the expert, I
told you, in this field.
So the idea is to
see the changes
in the mechanical
structure of the instrument
and it has certainly
effects on the sound,
the mechanical structure.
How it vibrate.
But it's not very related
in an obvious manner.
I'm -- we cannot tell from these
spectral measurements how it
affect the sound.
It's more complex than this.
I have to say that the violin
as an vibrating structure
is a very complex structure
to model properly.
And every violin is
slightly different,
even modern violins
are slightly different.
And it's very difficult to model
properly the influence of each
of the parameter, especially
when we go to the sound.
>> Unidentified Speaker: But
you would use the acoustical
information to help
set up the instrument.
Is that correct?
>> Jean-Philippe Echard: We --
for the moment we use it to
monitor the changes only.
We didn't go far
enough until now to --
it will need a dedicated
long term --
like a one-year study or
postdoc or something like that,
to study exactly the
effect of this parameter,
let's say the song post
position and length
on the changes of the structure.
It would need that to
understand exactly what we do.
And I showed you only an
other -- a simple spectrum,
if I may say, which is an
average spectrum of related
to the vibration
of the instrument.
But we would be also
available --
it would be also
possible to make maps.
So you would see the vibration
modes on how the plates deform
and vibrate at certain
frequency.
Which would help also but
this is some extra work,
a lot of computer
time and treatment.
>> Unidentified Speaker:
What processed was used
to remove the old image patina?
>> Fenella France: Question
was, what process was used
to remove the existing patina.
>> Jean-Philippe Echard: A
dedicated mixture of solvents
of three types, which were --
which are widely used
in painting conservation
and furniture conservation.
And I will not go into the
theoretical aspect of this
but it's filled like the
effect, the ways to use solvent
to clean surfaces is a
widely inspired from decades,
if not one century of solvent
studies to clean paintings.
So in this case I
will not say --
I mean, I don't have in mind
exactly the three solvents
that were mixed in
various ratios to adapt
to the reactivity
of the surface.
We want the material --
we wanted to remove but this
was done with this solvent
which were in contact on very
small areas using a swab --
a swab-- cotton swab
with the solvent
or tiny droplets using a micro
syringe to bring the solvent
and the contact time of the
solvent was controlled as well.
And then the material removed.
And all this was done under the
binocular microscope to control
at best with visual the thing.
In some tiny areas where the
material would be not responding
perfectly to the
solvent mixture,
we would use a mechanical
abrasion with a micro scalpel
as well under binocular control.
How do you call that?
A stereo microscope
is the proper one.
I'm sorry about that.
>> Unidentified Speaker:
Can I ask the [inaudible]
about how any storage
differences
or future conservation
recommendations would be
for these glasses and any
other glass objects compared
to any others?
>> Fenella France:
So the question was
about the storage
recommendations going forward.
Carol Lynn perhaps.
I know this is close
conservation.
>> Carol Lynn Ward
Bamford: Right.
We worked with the
conservation part of --
under the preservation
directorate.
And we have created
a modified cabinet,
a storage cabinet
that's gasketed.
And it has a glass
front so I can look in
and just eyeball things and
not pull out the drawer.
And it's -- the drawers
inside are perforated
to allow for air flow.
There are two fans in there that
also help circulate the air.
Then the flutes themselves,
so that's the cabinet
but within each flute we had
special cases made for --
or boxes made for
each individual flute,
that has like a micro filament
of like a cloth that sort
of suspends the flute.
And the ends of the
box are exposed or open
to allows much air
circulation as we can.
And then there is
silica gel at the bottom,
also at a controlled
set point --
or a relative set
point that we have.
So we actually have
started that.
We tested it for
quite a few months
and we've put the
flutes in this cabinet.
And we continue to monitor.
One of our monitor people
back there, Ben is here
and it's been fantastic
to work with them
to study the temperature
and humidity
that we're keeping in there.
>> Lynn Brostoff: I
would just like to add
that I think it's -- oh, yeah.
It's well known that when you
have glass that's unstable,
it's very important to keep --
to put things in an
environment that's very steady
so it's not cycling anymore.
And if you have hydrated
glass, it's quite dangerous
to lower the humidity too much.
So I don't remember the
recommended relative humidity
you have that you're
maintaining now.
But I do know, you know,
it's just kind of a warning
because metals are kept
relatively dry to --
so that they don't
corrode but the --
if the glass is already
hydrated, it could actually --
could be in an equilibrium
where the water is actually
holding together a certain
amount and could just
literally fall apart.
So it would be quite
dangerous to dry out glass.
And we did look at historical
records of the relative humidity
and temperature in the
previous vault setting.
And we did see a certain amount
of cycling especially,
that was seasonal.
So we've gone to great
effort to eliminate that kind
of variation in the atmosphere.
I mean, even just opening
the drawers and taking them
from the drawer into the room
for a researcher caused a spike.
So we went to great
lengths to eliminate that.
>> Unidentified Speaker:
What about my question?
>> Unidentified Speaker:
She answered your question.
>> Unidentified Speaker:
[Inaudible] question
about boots.
Is there a characteristic
fluorescence for potash flutes?
>> Fenella France: The
question was whether these is a
characteristic fluorescence
for potash flutes.
>> Lynn Brostoff: Yeah.
I think the literature
is a little bit confusing
about fluorescence of glass
and a lot of people felt
that it was just unpredictable.
But we are fortunate that
[inaudible] always put
that little dash
of manganese in.
And because of that
manganese we can tell
that it does have a
characteristic fluorescence
which was that yellowy green
color that Stephanie showed.
And in fact, it's very
important in UV examination
to use two wavelengths so you
can use long and short UV.
And the fluorescence is
a little bit different.
And we are now batting 100%
in predicting whether we
have a high leaded glass
or a potash glass for
[inaudible] flutes
because remember,
they're a formulation.
So that's not just
potassium and silicon,
there's a lot of other things.
Or it's not just
lead in silicon.
And yes, it's very
characteristically
that yellowy green color.
And the leaded ones are
also known in shortwave
to be what people call icy blue.
And the combination of
that pink and the icy blue
and the two wavelengths
is very definitive
for those highlighted glasses.
So as I said, we've been
using this technique
and we're literally 100%
spot on in predicting
which type of glass it is.
>> Fenella France: So I think
we'll just wrap up the questions
for now and you can catch some
of the speakers afterwards.
I think you'll join me in saying
that was a fantastic
group of presentations.
And I love the fact that
we saw so much influence
and importance placed
on the collaboration,
and the multidisciplinary
approach, and just the need
because we all have
slightly different expertises
and we all need to
work together.
And pull those -- the fact
that we're all doing
sometimes similar techniques,
sometimes different.
And new replications of those,
focusing on the non-invasive.
And also the educational
component and the dissemination
of research because
if we're going to use
or protect our cultural heritage
then we need to make sure
that we're sharing
this information.
So I just want to mention
that the next tops presentation
is preservation week
on April 23rd.
There'll be a number of events,
including a lunchtime lecture
and this is all on the website.
But also there will
be preservation tours
so have a look at the website.
But once again, please -- this
will bring to an end this part
of the afternoon and please
join me in thanking all
of our speakers very much.
This has been a presentation
of the Library of Congress.
Visit us at LOC.gov.