Wonders of chemistry--Origin, progress, and objects of alchemy--Art
of breathing fire--Employed by Barchochebas, Eunus, &c.--Modern
method--Art of walking upon burning coals and red-hot iron, and of
plunging the hands in melted lead and boiling water--Singular property
of boiling tar--Workmen plunge their hands in melted copper--Trial
of ordeal by fire--Aldini’s incombustible dresses--Examples of their
wonderful power in resisting flame--Power of breathing and enduring
air of high temperatures--Experiments made by Sir Joseph Banks, Sir
Charles Blagden, and Mr. Chantrey.
Chemistry has from its infancy been pre-eminently the science of
wonders. In her laboratory the alchemist and the magician have revelled
uncontrolled, and from her treasures was forged the sceptre which was
so long and so fatally wielded over human reason. The changes which
take place in the bodies immediately around us are too few in number
and too remote from observation to excite much of our notice; but when
the substances procured directly from nature, or formed casually by
art, become objects of investigation, they exhibit in their simple or
combined actions the most extraordinary effects. The phenomena which
they display, and the products which they form, so little resemble
those with which we are familiar, that the most phlegmatic and the
least speculative observer must have anticipated from them the creation
of new and valuable compounds. It can scarcely, therefore, be a
matter of surprise that minds of the highest order, and spirits of
the loftiest ambition, should have sought in the transmutations of
chemistry for those splendid products which were conceived to be most
conducive to human happiness.
The disciple of Mammon grew pale over his crucible in his ardour to
convert the baser metals into gold; the philosopher pined in secret
for the universal solvent which might develop the elements of the
precious stones and yield to him the means of their production; and the
philanthropist aspired after a universal medicine, which might arrest
disease in its course, and prolong indefinitely the life of man. To
us, who live under the meridian of knowledge, such expectations must
appear as presumptuous as they were delusive; but when we consider
that gold and silver were actually produced by chemical processes from
the rude ores of lead and copper--that some of the most refractory
bodies had yielded to the disintegrating and solvent powers of chemical
agents, and that the mercurial preparations of the Arabian physicians
had operated like charms in the cure of diseases that had resisted
the feeble medicines of the times, we may find some apology for the
extravagant expectations of the alchemists.
An object of lofty pursuit, even if it be one of impossible attainment,
is not unworthy philosophical ambition. Though we cannot scale the
summit of the volcanic cone, we may yet reach its heaving flanks; and
though we cannot decompose its loftiest fires, we may yet study the
lava which they have melted and the products which they have sublimed.
In like manner, though the philosopher’s stone has not been found,
chemistry has derived rich accessions from its search;--though the
general solvent has not been obtained, yet the diamond and the gems
have surrendered to science their adamantine strength;--and though
the elixir of life has never been distilled, yet other medicines have
soothed the “ills which flesh is heir to,” and prolonged in no slight
degree the average term of our existence.
Thus far the pursuits of the alchemist were honourable and useful;
but when his calling was followed, as it soon was, by men prodigal
of fortune and of character, science became an instrument of crime;
secrets unattained were bartered for the gold of the credulous and the
ignorant, and books innumerable were composed to teach these pretended
secrets to the world. An intellectual reaction, however, soon took
place; and those very princes who had sought to fill their exhausted
treasuries at the furnace of the chemist, were the first to enact
laws against the frauds which they had encouraged, and to dispel the
illusions which had so long deceived their subjects.
But even when the moral atmosphere of Europe was thus disinfected,
chemistry supplied the magician with his most lucrative wonders, and
those who could no longer delude the public with dreams of wealth and
longevity, now sought to amuse and astonish them by the exhibition
of their skill. The narrow limits of this volume will not permit me
to give even a general view of those extraordinary effects which
this popular science can display. I must therefore select from its
inexhaustible stores those topics which are most striking in their
results, and most popular in their details.
One of the most ancient feats of magic was the art of breathing
flame,--an art which even now excites the astonishment of the vulgar.
During the insurrection of the slaves in Sicily, in the second century
before Christ, a Syrian named Eunus acquired by his knowledge the rank
of their leader. In order to establish his influence over their minds,
he pretended to possess miraculous power. When he wished to inspire his
followers with courage, he breathed flames or sparks among them from
his mouth, at the same time that he was rousing them by his eloquence.
St. Jerome informs us that the Rabbi Barchochebas, who headed the Jews
in their last revolt against Hadrian, made them believe that he was the
Messiah, by vomiting flames from his mouth; and at a later period, the
Emperor Constantius was thrown into a state of alarm when Valentinian
informed him that he had seen one of the body-guards breathing out
fire and flames. We are not acquainted with the exact methods by which
these effects were produced; but Florus informs us that Eunus filled
a perforated nut-shell with sulphur and fire, and having concealed it
in his mouth, he breathed gently through it while he was speaking.
This art is performed more simply by the modern juggler. Having rolled
together some flax or hemp, so as to form a ball the size of a walnut,
he sets it on fire, and allows it to burn till it is nearly consumed:
he then rolls round it while burning some additional flax, and by these
means the fire may be retained in it for a considerable time. At the
commencement of his exhibition he introduces the ball into his mouth,
and while he breathes through it the fire is revived, and a number
of burning sparks are projected from his mouth. These sparks are too
feeble to do any harm, provided he inhales the air through his nostrils.
The kindred art of walking on burning coals or red-hot iron remounts to
the same antiquity. The priestesses of Diana at Castabala in Cappadocia
were accustomed, according to Strabo, to walk over burning coals; and
at the annual festival which was held in the temple of Apollo on Mount
Soracte in Etruria, the Hirpi marched over burning coals, and on this
account they were exempted from military service, and received other
privileges from the Roman Senate. This power of resisting fire was
ascribed even by Varro to the use of some liniment with which they
anointed the soles of their feet.
Of the same character was the art of holding red-hot iron in the hands
or between the teeth, and of plunging the hands into boiling water or
melted lead. About the close of the seventeenth century, an Englishman
of the name of Richardson rendered himself famous by chewing burning
coals, pouring melted lead upon his tongue, and swallowing melted
glass. That these effects are produced partly by deception, and partly
by a previous preparation of the parts subjected to the heat, can
scarcely admit of a doubt. The fusible metal, composed of mercury,
tin, and bismuth, which melts at a low temperature, might easily have
been substituted in place of lead; and fluids of easy ebullition may
have been used in place of boiling water. A solution of spermaceti
or sulphuric ether, tinged with alkanet root, which becomes solid at
50° of Fahrenheit, and melts and boils with the heat of the hand, is
supposed to be the substance which is used at Naples when the dried
blood of St. Januarius melts spontaneously, and boils over the vessel
which contains it.
But even when the fluid requires a high temperature to boil, it may
have other properties, which enable us to plunge our hands into it
with impunity. This is the case with boiling tar, which boils at a
temperature of 220°, even higher than that of water. Mr. Davenport
informs us, that he saw one of the workmen in the Royal Dock-yard at
Chatham immerse his naked hand in tar of that temperature. He drew up
his coat-sleeves, dipped in his hand and wrist, bringing out fluid tar,
and pouring it off from his hand as from a ladle. The tar remained in
complete contact with his skin, and he wiped it off with tow. Convinced
that there was no deception in this experiment, Mr. Davenport immersed
the entire length of his fore-finger in the boiling cauldron, and
moved it about a short time before the heat became inconvenient. Mr.
Davenport ascribes this singular effect to the slowness with which
the tar communicates its heat, which he conceives to arise from the
abundant volatile vapour which is evolved, “carrying off rapidly
the caloric in a latent state, and intervening between the tar and
the skin, so as to prevent the more rapid communication of heat.”
He conceives also, that when the hand is withdrawn, and the hot tar
adhering to it, the rapidity with which this vapour is evolved from
the surface exposed to the air cools it immediately. The workmen
informed Mr. Davenport that, if a person put his hand into the cauldron
with his glove on, he would be dreadfully burnt; but this extraordinary
result was not put to the test of observation.
But though the conjurors with fire may have availed themselves of
these singular properties of individual bodies, yet the general secret
of their art consisted in rendering the skin of the exposed parts
callous and insensible to heat,--an effect which may be produced by
continually compressing or singeing them till the skin acquires a horny
consistence. A proof of this opinion is mentioned by Beckmann, who
assures us, that in September, 1765, when he visited the copper-works
at Awestad, one of the workmen, bribed by a little money to drink,
took some of the melted copper in his hand, and, after showing it to
the company, threw it against a wall. He then squeezed the fingers of
his horny hand close to each other, held it a few minutes under his
arm-pit, to make it perspire, as he said, and taking it again out, drew
it over a ladle filled with melted copper, some of which he skimmed
off, and moved his hand backwards and forwards very quickly by way of
ostentation. During this performance, M. Beckmann noticed a smell like
that of singed horn or leather, though the hand of the workman was
not burned. This callosity of the skin may be effected by frequently
moistening it with dilute sulphuric acid. Some allege that the juices
of certain plants produce the same effect, while others recommend the
frequent rubbing of the skin with oil. The receipt given by Albertus
Magnus for this purpose was of a different nature. It consisted of a
non-conducting calcareous paste, which was made to adhere to the skin
by the sap of the marsh-mallow, the slimy seeds of the flea-bane, and
the white of an egg.
As the ancients were acquainted with the incombustibility of asbestos
or amianthus, and the art of weaving it into cloth, it is highly
probable that it was employed in the performance of some of their
miracles, and it is equally probable that it was subsequently used,
along with some of the processes already described, in enabling the
victims of superstition to undergo without hazard the trial of ordeal
by fire. In every country where this barbarous usage prevailed, whether
in the sanctuary of the Christian idolater, or in the pagan temple of
the Bramin, or under the wild orgies of the African savage, Providence
seems to have provided the means of meeting it with impunity. In
Catholic countries this exculpatory judgment was granted chiefly
to persons in weak health, who were incapable of using arms, and
particularly to monks and ecclesiastics, who could not avail themselves
of the trial by single combat. The fire ordeal was conducted in the
church under the inspection of the clergy: mass was at the same time
celebrated, and the iron and the victims were consecrated by the
sprinkling of holy water. The preparatory steps were also under the
direction of the priests. It was necessary that the accused should be
placed three days and three nights under their care, both before and
after the trial. Under the pretence of preventing the defendant from
preparing his hands by art, and in order to ascertain the result of
the ordeal, his hands were covered up and sealed during the three days
which preceded and followed the fiery application; and it has been
plausibly conjectured by Beckmann, that during the first three days the
preventive was applied to those whom they wished to acquit, and that
the last three days were requisite to bring back the hands to their
natural condition. In these and other cases, the accused could not
have availed himself directly of the use of asbestos gloves, unless we
could suppose them so made as to imitate the human skin at a distance;
but the fibres of that mineral may have been imbedded in a paste which
applied itself readily to all the elevations and depressions of the
skin.
In our own times the art of defending the hands and face, and indeed
the whole body, from the action of heated iron and intense fire, has
been applied to the nobler purpose of saving human life, and rescuing
property from the flames. The revival and the improvement of this art
we owe to the benevolence and the ingenuity of the Chevalier Aldini of
Milan, who has travelled through all Europe to present this valuable
gift to his species. Sir H. Davy had long ago shown that a safety
lamp for illuminating mines, containing inflammable air, might be
constructed of wire-gauze alone, which prevented the flame within,
however large or intense, from setting fire to the inflammable air
without. This valuable property, which has been long in practical use,
he ascribed to the conducting and radiating power of the wire-gauze,
which carried off the heat of the flame, and deprived it of its power.
The Chevalier Aldini conceived the idea of applying the same material,
in combination with other badly conducting substances, as a protection
against fire. The incombustible pieces of dress which he uses for the
body, arms, and legs, are formed out of strong cloth, which has been
steeped in a solution of alum, while those for the head, hands, and
feet, are made of cloth of asbestos or amianthus. The head-dress is
a large cap which envelops the whole head down to the neck, having
suitable perforations for the eyes, nose, and mouth. The stockings and
cap are single, but the gloves are made of double amianthus cloth, to
enable the fireman to take into his hand burning or red hot bodies. The
piece of ancient asbestos cloth preserved in the Vatican was formed,
we believe, by mixing the asbestos with other fibrous substances;
but M. Aldini has executed a piece of nearly the same size, nine
feet five inches long and five feet three inches wide, which is much
stronger than the ancient piece, and possesses superior qualities,
in consequence of having been woven without the introduction of any
foreign substance. In this manufacture the fibres are prevented from
breaking by the action of steam, the cloth is made loose in its fabric,
and the threads are about the fiftieth of an inch in diameter.
The metallic dress which is superadded to these means of defence
consists of five principal pieces, viz. a _casque_ or cap, with a mask
large enough to leave a proper space between it and the asbestos cap; a
cuirass with its brassets; a piece of armour for the trunk and thighs;
a pair of boots of double wire-gauze; and an oval shield 5 feet long
by 2½ wide, made by stretching the wire-gauze over a slender frame of
iron. All these pieces are made of iron wire-gauze, having the interval
between its threads the twenty-fifth part of an inch.
In order to prove the efficacy of this apparatus, and inspire the
firemen with confidence in its protection, he showed them that a finger
first enveloped in asbestos, and then in a double case of wire-gauze,
might be held a long time in the flame of a spirit-lamp or candle
before the heat became inconvenient. A fireman having his hand within
a double asbestos glove, and its palm protected by a piece of asbestos
cloth, seized with impunity a large piece of red-hot iron, carried it
deliberately to the distance of 150 feet, inflamed straw with it, and
brought it back again to the furnace. On other occasions the fireman
handled blazing wood and burning substances, and walked during five
minutes upon an iron grating placed over flaming fagots.
In order to show how the head, eyes, and lungs are protected, the
fireman put on the asbestos and wire-gauze cap, and the cuirass, and
held the shield before his breast. A fire of shavings was then lighted,
and kept burning in a large raised chafing-dish; the fireman plunged
his head into the middle of the flames with his face to the fuel, and
in that position went several times round the chafing-dish for a period
longer than a minute. In a subsequent trial, at Paris, a fireman placed
his head in the middle of a large brazier filled with flaming hay and
wood, as in Fig. 77, and resisted the action of the fire during five or
six minutes, and even ten minutes.
[Illustration: _Fig. 77._]
In the experiments which were made at Paris in the presence of a
committee of the Academy of Sciences, two parallel rows of straw and
brushwood, supported by iron wires, were formed at the distance of
three feet from each other, and extended thirty feet in length. When
this combustible mass was set on fire, it was necessary to stand at
the distance of eight or ten yards to avoid the heat. The flames from
both the rows seemed to fill up the whole space between them, and rose
to the height of nine or ten feet. At this moment six firemen, clothed
in the incombustible dresses, and marching at a slow pace behind each
other, repeatedly passed through the whole length between the two rows
of flame, which were constantly fed with additional combustibles.
One of the firemen carried on his back a child eight years old, in a
wicker-basket covered with metallic gauze, and the child had no other
dress than a cap made of amianthine cloth.
In February, 1829, a still more striking experiment was made in the
yard of the barracks of St. Gervais. Two towers were erected two
stories high, and were surrounded with heaps of inflamed materials,
consisting of fagots and straw. The firemen braved the danger with
impunity. In opposition to the advice of M. Aldini, one of them, with
the basket and child, rushed into a narrow place, where the flames were
raging eight yards high. The violence of the fire was so great that he
could not be seen, while a thick black smoke spread around, throwing
out a heat which was unsupportable by the spectators. The fireman
remained so long invisible that serious doubts were entertained of his
safety. He at length, however, issued from the fiery gulf uninjured,
and proud of having succeeded in braving so great a danger.
It is a remarkable result of these experiments, that the firemen
are able to breathe without difficulty in the middle of the flames.
This effect is owing not only to the heat being intercepted by the
wire-gauze as it passes to the lungs, in consequence of which its
temperature becomes supportable, but also to the singular power which
the body possesses of resisting great heats, and of breathing air of
high temperatures.
A series of curious experiments were made on this subject by M. Tillet
in France, and by Dr. Fordyce and Sir Charles Blagden in England. Sir
Joseph Banks, Dr. Solander, and Sir Charles Blagden entered a room
in which the air had a temperature of 198° Fahr., and remained ten
minutes; but as the thermometer sank very rapidly, they resolved to
enter the room singly. Dr. Solander went in alone, and found the heat
210°, and Sir Joseph entered when the heat was 211°. Though exposed
to such an elevated temperature, their bodies preserved their natural
degree of heat. Whenever they breathed upon a thermometer it sank
several degrees: every expiration, particularly if strongly made, gave
a pleasant impression of coolness to their nostrils, and their cold
breath cooled their fingers whenever it reached them. On touching his
side, Sir Charles Blagden found it cold like a corpse, and yet the
heat of his body under his tongue was 98°. Hence they concluded that
the human body possesses the power of destroying a certain degree
of heat when communicated with a certain degree of quickness. This
power, however, varies greatly in different media. The same person
who experienced no inconvenience from air heated to 211°, could just
bear rectified spirits of wine at 130°, cooling oil at 129°, cooling
water at 123°, and cooling quicksilver at 117°. A familiar instance of
this occurred in the heated room. All the pieces of metal there, even
their watch-chains, felt so hot that they could scarcely bear to touch
them for a moment, while the air from which the metal had derived all
its heat was only unpleasant. Messrs. Duhamel and Tillet observed,
at Rochefoucault in France, that the girls who were accustomed to
attend ovens in a bakehouse were capable of enduring for ten minutes a
temperature of 270°.
The same gentlemen who performed the experiments above described
ventured to expose themselves to still higher temperatures. Sir Charles
Blagden went into a room where the heat was 1° or 2° above 260°, and
remained eight minutes in this situation, frequently walking about
to all the different parts of the room, but standing still most of
the time in the coolest spot, where the heat was above 240°. The air,
though very hot, gave no pain, and Sir Charles and all the other
gentlemen were of opinion that they could support a much greater heat.
During seven minutes Sir C. Blagden’s breathing continued perfectly
good, but after that time he felt an oppression in his lungs, with
a sense of anxiety, which induced him to leave the room. His pulse
was then 144, double its ordinary quickness. In order to prove that
there was no mistake respecting the degree of heat indicated by the
thermometer, and that the air which they breathed was capable of
producing all the well-known effects of such a heat on inanimate
matter, they placed some eggs and a beef-steak upon a tin frame near
the thermometer, but more distant from the furnace than from the wall
of the room. In the space of twenty minutes the eggs were roasted quite
hard, and in forty-seven minutes the steak was not only dressed, but
almost dry. Another beef-steak, similarly placed, was rather overdone
in thirty-three minutes. In the evening, when the heat was still more
elevated, a third beef-steak was laid in the same place, and as they
had noticed that the effect of the hot air was greatly increased by
putting it in motion, they blew upon the steak with a pair of bellows,
and thus hastened the dressing of it to such a degree that the
greatest portion of it was found to be pretty well done in thirteen
minutes.
Our distinguished countryman, Sir F. Chantrey, has very recently
exposed himself to a temperature still higher than any which we have
mentioned. The furnace which he employs for drying his moulds is about
14 feet long, 12 feet high, and 12 feet broad. When it is raised to
its highest temperature, with the doors closed, the thermometer stands
at 350°, and the iron floor is red hot. The workmen often enter it
at a temperature of 340°, walking over the iron floor with wooden
clogs, which are of course charred on the surface. On one occasion
Sir F. Chantrey, accompanied by five or six of his friends, entered
the furnace, and, after remaining two minutes, they brought out a
thermometer which stood at 320°. Some of the party experienced sharp
pains in the tips of their ears, and in the septum of the nose, while
others felt a pain in their eyes.