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In spite of Egypt is generally recognized as the mother of the chemical and
alchemical arts, but unfortunately her monuments and literature have left little
of the early records which explain these arts.
Some of these ideas have been
transmitted to us through Greek and Roman sources but the character of these
sources do not enable us to discriminate between the matter derived from Egypt
and the confused interpretation or additions of the early Greek alchemists.
The stories told us that about 290 A.D. the Emperor Diocletian passed a
decree compelling the destruction of the works upon alchemical arts and on gold
and silver throughout the empire, so that it should not be the makers of gold
and silver to amass riches which might enable them to organize revolts against
the empire. This decree resulted in the disappearance of a mass of literature
which doubtless would have furnished us with much of interest in the early
history of chemical arts and ideas.
The French chemist Marcelin Berthelot who was interested in the history of
early chemistry, subjected this Papyrus to critical analysis and published a
translation of his results into French with extensive notes and
commentaries
On the basis of philological and paleography evidence, he
concluded its date is about the end of the third century A. D. It is, however,
manifestly a copy of a work previously written, as slight errors evidently due
to a copyist, are found. That the original is later than the first century A. D.
is certain, as there are included in it extracts from the Materia Medica
of Dioscorides. The work is a collection of chemical recipes and directions for
:
1. Making metallic alloys,
2. Imitations of gold, silver or electrum,
3. Dyeing and other related arts.
In 1913 at Upsala, Otto Lagercrantz published the Greek text with critical
commentary and with translation into German of a similar Egyptian papyrus, the "
Papyrus Graecus Holmiensis." This work like the Leyden manuscript is a
collection of recipes for alloys, metal working, dyeing, imitations of precious
stones and similar arts. Investigation developed that this manuscript also came
from the Swedish vice consul at Alexandria, d'Anastasy, presented by him to the
Swedish Academy of Antiquities of Stockholm. Here it slumbered apparently
unnoticed until 1906 when it was transferred to the Victoria Museum at
Upsala.
Examination and comparison with the Leyden Papyrus made it evident
that the new papyrus was not only identical, but in all probability was in part
at least written by the same hand.
Both papyri were in remarkably well
preserved condition. Both gave internal evidence of having been copied from
other originals. Berthelot has suggested that the Papyrus X had been preserved
in the mummy-case of an Egyptian chemist, and Lagercrantz agreed in the opinion
and is convinced that the two works were the property of the same person, and
that these copies were probably made as deluxe copies for the purpose of being
entombed with their former owner in accordance with a common custom of placing
in the tomb articles formerly owned or used by the deceased.
The two
manuscripts were taken together from an interesting collection of laboratory
recipes of the kinds which Diocletian ordered destroyed and which apparently
were very generally destroyed. The date ascribed to them is about the time of
the decree of Diocletian, and it may be presumed that, in the mummy case, they
escaped the execution of that decree.
The laboratory manuals from which these
copies were made, were written not for public information but for the guidance
of the workers. The recipes themselves are often very detailed directions, but
often also were mere hints or suggestions, sometimes elliptical to such an
extent as to give no clear idea of the process as carried out.
The Leyden
papyrus comprises about seventy-five recipes pertaining to the making of alloys,
for soldering metals, for coloring the surfaces of metals, for testing the
quality of or purity of metals, or for imitating the precious metals.
There
are fifteen recipes for writing in gold or silver or in imitation of gold and
silver writing. There are eleven recipes for dyeing stuffs in purple or other
colors. The last eleven paragraphs are extracts from the Materia Medica
of Dioscorides, relating to the minerals or materials used in the processes
involved.
Berthelot notes that the artisan who used these notes while a
practical worker in metals, especially the metals used by the jewelers, seemed
to be a stranger to the arts of enamels and of artificial gems. It is,
therefore, of great interest to discover that the Stockholm papyrus supplements
the Leyden recipes in this direction. The Stockholm manuscript contains in all
about a hundred and fifty recipes. Of these, only nine deal with metals and
alloys, while over sixty relate to dyeing and about seventy to the production of
artificial gems. Some ten others deal with the whitening of off-color pearls or
the making of artificial pearls.
It has been noticed that there is
practically only a duplication of recipes contained in each of the manuscripts,
and very similar recipes occur in both. The recipes in both are empirical with
no evidences of any occult theories, nor any of that obscurity of language which
is so characteristic of the later alchemists.
The parts dealing with the
metals are largely concerned with transmutation of gold, silver or electrum from
cheaper materials, or with giving an external or superficial color of gold or
silver to cheaper metal. There seems to be no self-deception in those matters.
On the contrary, there are often claims that the product will answer the usual
tests for genuine products, or that they will deceive even the artisans. The
vocabulary of materials used is practically that of Dioscorides, with few
changes in the meaning of such terms as are used by him, although at times the
Latin equivalents of Vitruvius and Pliny have been employed.
There is little
to be found in these manuscripts which suggests that there has been any advance
in the practical arts as known in the times of Dioscorides and Pliny and which
had been less specifically described by them, but the papyri in the more
definite and detailed directions they give, throw a very interesting light upon
the somewhat limited fields of industrial chemistry, of which they treat.
Examples will best serve to illustrate the character of the recipes and of
the knowledge of practical chemistry which underlies them.
The following are
some selections of the Papyrus of Leyden, as found in the previously mentioned
translation of Berthelot:
Manufacture of asem (eleetrum)
Tin, 12 drachmas; quicksilver, 4
drachmas; earth of Chios, 2 drachmas. To the melted tin add the powdered earth,
then add the mereury, stir with an iron, and put it into use.
[This, then, is
a tin amalgam intended to give the appearance of asem or silver. The earth of
Chios as described by Pliny appears to have been a white clay. Pliny says it was
used by women as a cosmetic.]
The doubling (diplosis) of asem
Take refined copper (chalchos) 40
drachmas, asem 8 drachmas, button tin 40 drachmas. The copper is first melted
and after two heatings the tin and finally the asem is added. When all is
softened, remelt several times and cool by means of the preceding composition.
Clean with coupholith (tale or selenite according to Berthelot). The tripling
(triplosis) is effected by the same process, the weights being proportioned in
conformity with what has been directed above.
[This recipe would yield a pale
yellow bronze containing mercury if, as seems probable.]
Purification of tin
Liquid pitch and bitumen, one part of each.
Throw it on and melt and stir. Of dry pitch 20 drachmas, bitumen 12
drachmas.
[This is manifestly a process of obtaining an unoxidized clean tin
for further use.]
Manufacture of asem
Take soft tin in small pieces, four times
purified. Take of it four parts and three parts of pure white Copper (or bronze,
"chalchos"), and one part of asem. Melt and after casting, clean several times
and make what you will with it. This will be asem of the first quality which
will deceive even the artisans.
[Copper was whitened by the ancients
sometimes by alloying with arsenic. A recipe in this papyrus gives directions
for this whitening of copper.]
Augmentation of gold
To augment gold, take Thracian cadmia, make
the mixture with the cadmia in crusts; or cadmia of Gaul misy and sinopian red,
equal parts to that of gold. When the gold has been put into the furnace and has
become of good color, throw in these two ingredients and removing [the gold] let
it cool and the gold will be doubled.
[Cadmia, it will be remembered, is the
impure zinc oxide, containing sometimes lead and copper oxides, from the
furnaces in which brass was smelted. Misy was the partly oxidized iron or copper
pyrites, essentially basic sulphates of iron and copper. Synopian red was
haematite. This mixture, assuming the reducing action of the fuel in the
furnace, or of any other reducing agent not specified in the recipe would yield
an alloy of gold and zinc, with some copper and perhaps some lead.]
To make asem
Carefully purify lead with pitch and bitumen, or tin
as well; mix cadmia and litharge in equal parts with the lead. Stir till the
mixture becomes solid. It can be used like natural asem.
[Reduction in the
furnace must here also be assumed. The soft white alloy so obtained must have
been a cheap and poor substitute for electrum or silver.]
Preparation of chrysocolla (solder for gold)
The solder for gold is
prepared thus: Copper of Cyprus 4 parts, asem 2 parts, gold 1 part. The copper
is melted first, then the asem and finally the gold.
[It will be recalled
that the term "chrysocolla" was applied also to malachite, verdigris and copper
acetate, all of these being used for soldering gold.]
To determine the purity of tin
Having melted it, place paper
(papyrus) underneath it and pour it out.
[If the paper is scorched the tin
contains lead.]
To make asem black as obsidian
Asem, 2 parts, lead, 4 parts. Place
in an earthen vessel, throw on it a triple weight of native sulphur, and having
put into the furnace, melt. After withdrawing from the furnace, beat and make
what you will. If you wish to make figured objects of beaten or cast metal,
polish and cut it. It does not rust.
[This process yields a metallic mass
blackened with sulphides of lead and silver, similar to the black silver bronze
as described by Pliny.]
To give objects of copper the appearance of gold, so
that neither the feel, nor rubbing on the touchstone can detect it, to serve
especially for a ring of fine appearance.
Gold and lead are reduced to a fine
powder like flour, 2 parts lead to 1 of gold. When mixed, they are mixed with
gum and the ring covered with this mixture and heated. The operation is repeated
several times till the article has taken the color. It is difficult to detect
because rubbing gives the mark (or "scratch") of a genuine article, and the heat
consumes the lead but not the gold.
[This is an interesting process of gold
plating by using lead instead of mercury, the lead being oxidized and
volatilized in the heating.]
Test for purity of gold
Remelt and heat it. If pure, it keeps its
color after heating, and remains like a coin. If it becomes whiter, it contains
silver, if it becomes rough and hard, it contains copper and tin, if it softens
and blackens it contains lead.
To gild silver in a durable way
Take quicksilver and gold leaf,
making to the consistency of wax. Clean the vase with alum, and taking a little
of the waxy material spread it on the vase with the polisher and let it stand to
fix. Do this five times. Take the vase with a linen cloth so that it be not
soiled, and removing it from the coals, prepare ashes, smooth with the polisher
and use it as a gold vase. It will stand the test for real gold.
[The recipes
for writing with letters of gold vary much according to the material upon which
the were to be applied, as also with respect to their relative durability.]
To write in letters of gold
Take quicksilver, pour it into a
suitable vase and add gold leaf. When the gold appears dissolved in the
quicksilver, shake well, add a little gum, one grain for example, and letting it
stand, write in letters of gold.
Cheaper imitations of gold writing were also used as illustrated in the
following:
Orpiment of gold color, 20 drachmas; powdered glass, 4 staters; or
white of egg, 2 staters; white gum, 20 staters; safran.....
After writing,
let it dry and polish with a tooth.
[An animal's tooth used by jewelers for
polishing up till now. In other recipes, the yellow or gold color is obtained by
sulphur mixed with gum; the "bile of the tortoise," or of the calf, "very
bitter," serves also for the color. These may be secret trade names for some
substances of different character.]