Using Chemistry to Uncover a History: Is this an early map of North

Using Chemistry to Uncover a
History: Is this an early map of North
America – or not?
Anal. Chem. 2002, 74, 3658-3661
spectroscopy • archeological chemistry • analytical chemistry
Just before Columbus Day in 1965, Yale University unveiled
a spectacular item in its collection of rare manuscripts: a map
of North America dated before Columbus. The Vinland Map
appeared to be the record of a journey by Leif Eriksson to the
New World and was reportedly insured for more than $25
million. Interestingly, the map’s provenance was thin. It
appeared to have been discovered in the leaves of another
manuscript in the early 20th century, leaving its whereabouts
for the previous 500 years unknown. Paleographers often
view documents without a strong provenance as forgeries
until proven otherwise, and the Vinland map was no
exception. Some scholars were suspicious of oddities in the
Latin such as rendering Eriksson as Ericsonnius instead of
Erici filius, others point to matching worm holes in the map
and the documents inside which reportedly it had been found.
Lacking definitive historical evidence, chemists entered the
fray. In the 1970s examination of the map revealed the
presence of anatase, a pigment unknown in the period during
which the map was supposed to have been produced. Yet
subsequent radiocarbon dating of the parchment indicated that
it, at least, was of the appropriate age. Further studies of the
inks and pigments on the Vinland map and the Tartar Relation
(another document found with it) lent credence to the theory
that the map is a hoax. The scholarly exchange is getting
heated, witness the beginning of a letter from Prof. Robin
Clark to the editor of the journal Analytical Chemistry:
“Unfortunately [Olin’s] article is based on speculation, lacks
logic, and lacks either new information or new insight on the
ink, consisting merely of a rewriting of her earlier
publications. Its publication has provided the scientific and
popular press with fuel with which to fire further, entirely
unjustified, controversy on this subject.”
A section of the Vinland Map
Palæography is the study of
ancient manuscripts as well as
the science and art of
deciphering and determining
the date of ancient writings or
systems of writing.
© 2004 Michelle M. Francl. May be reproduced for use in an individual classroom. May not be sold or used in other collections
without the express permission of the author. These materials were produced as part of “P-Chem with a Purpose,” funded by the
National Science Foundation, grant DUE-0340873.
Using Chemistry to Construct a History
Anal. Chem. 2002, 74, 3658-3661
Modern iron gallotannate ink
Tannic acid, 11.7 g
Gallic acid crystals, 3.8 g
Ferrous sulphate crystals, 15.0 g
Hydrochloric acid, "dilute", S.S.P.,
12.5 g
Carbolic acid, 12.5 g
Dye (C.I. 707; Sch. 539), 1.0 g
Water (distilled is best) to make a
volume of 1 liter at 20oC
Analysis of Pigmentary Materials on the
Vinland Map and Tartar Relation by Raman
Microprobe Spectroscopy
Katherine L. Brown and Robin J.H. Clark
From the National Bureau of
Standards, 1936, developed
originally for post-office lobby
ink.
Questions and Problems
The questions and problems below are based on the paper cited. They
are meant to encourage you to read the paper critically, you may need to
consult other articles in the literature to answer these question. If you
were the editor of the journal, what questions might you have for the
authors?
Iron gall ink
To make good ink.
Take 5 ounces of the best
Nuttgalls, break them in a
mortar but not in small pieces,
then put the gall into one quart
of clear rain water or soft
spring water, let them stand 4
or 5 days shaking them often,
then take 2 ounces of white
gum arabick, 1 ounce of
double refined sugar, 1 piece
of indigo and put in the same
and shake them well and let
them stand 4 or 5 days more.
Then take 2 ounces of good
green copperis the larger the
better and having first washed
off the filth put in to the rest
and also a piece of clear gum,
about as big as a walnut to set
the colour and it will be fit for
use.
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1. What is Raman spectroscopy? Why use this and not IR?
Sketch a Raman apparatus.
2. The use of vermilion on rubric of the Tartar Relation is
confirmed by the presence of three lines attributed to
HgS. Why should this diatomic have more than one
vibrational line?
3. The authors note that some regions of the manuscript
exhibited significant fluorescence and suggest this is
evidence of organic materials present on the map. Why
would the inorganic materials not fluoresce?
4. According to the authors, anatase, the pigment of interest,
is not the most common form of TiO2 found in nature.
What is and how does its structure differ from anatase?
5. Another titanium ore, ilmenite, is also suggested as a
source of the residues seen on the map. What is the form
of this mineral? Can you propose a mechanism for the
conversion of ilmenite to anatase in iron gall ink?
6. The authors lament their inability to use a Raman
microscope to study the map. What would be the
advantage to using that apparatus?
7. The radiocarbon dating experiments referred to by the
authors have now been published, why are they not
definitive? What is the advantage of the Raman
spectroscopy relative to radiocarbon techniques?
8. Would carbon-14 dating of the ink be helpful? Why do
Using Chemistry to Construct a History
you think it hasn’t been done yet?
9. What oxidation product in the iron gall ink is likely to
produce the yellow color?
10. Based on this paper, is the Tartar Relation a hoax, too?
11. What should Yale do with the map? Do you agree with
Clark that the controversy is overblown?
Vermilion is a red pigment
derived from cinnabar. The
name derives from the Latin
for worms. The Romans made
this color from dried worms
that infested oak trees.
Further Reading
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Beinecke Library web site. Search their digital image
collection for images of the Vinland Map.
http://beinecke.library.yale.edu
Maps, Myths and Men: The Story of the Vinland
Map, K. Seaver (Stanford University Press, 2004)
details the modern history of the map and the
controversy. The Vinland Map and the Tartar
Relation, T. Cahill and B. Kusko (Yale University
Press, 1995) gives the case for the authenticity of the
map.
“Was the Vinland Map faked to tweak the Nazis?” E.
Eakins, in the New York Times, September 14, 2002.
"The Vinland Map: Still a Forgery,” K. Towe, Accts.
Chem. Res. 1990, 23, 84-87.
The controversy plays out in Analytical Chemistry:
“Evidence That the Vinland Map Is Medieval”, J.S.
Olin, Anal. Chem. 2003, 75, 6745. “The Vinland Map
- Still a 20th Century Forgery,” R. J. H. Clark, Anal.
Chem. 2004, 76, 2423. “The Vinland Map Ink is
NOT Medieval”, K. M. Towe, Anal. Chem. 2004, 76,
863-865.
“Determination of the Radiocarbon Age of
Parchment of the Vinland Map,” D. J. Donahue, J.S.
Olin, G. Harbottle, Radiocarbon 2002, 44, 45–52.
Information on iron gall inks:
http://www.knaw.nl/ecpa/ink/index.html
A web exhibit on the map, which includes
photographs of the Raman investigation:
http://webexhibits.org/vinland/
Blots Pens in the UK sells iron gall ink prepared
according to a 1540 recipe.
http://www.blotspens.co.uk/
India Ink
To make inke upon a
suddaine, to serve in an
extremetie.
Take a wax candle, and light it,
hold it under a cleane bason or
a candlesticke, till the smoke
of the candle hangeth thereon,
then put a little warme gum
water into it, which tempered
together will be good inke.
From A Booke of Secrets,
ca. 1596.
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