Scientific American Supplement No. 360, November 25, 1882

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All admired Luther. Conduct was three-fourths of life, and a man who
worked for conduct, therefore, worked for more than a man who worked for
intelligence. But having promised this, it might be said that the Luther
of the eighteenth century and of the cultivated classes was Voltaire.
As Luther had an antipathy to what was immoral, so Voltaire had an
antipathy to what was absurd, and both of them made war upon the object
of their antipathy with such masterly power, with so much conviction,
so much energy, so much genius, that they carried their world with
them--Luther his Protestant world, and Voltaire his French world--and
the cultivated classes throughout the continent of Europe generally.

Voltaire had more than negative lucidity; he had the large and true
conception that a number and equilibrium of activities were necessary
for man. "_Il faut douner a notre ame toutes les formes possibles_"
was a maxim which Voltaire really and truly applied in practice,
"advancing," as Michelet finely said of him, in every direction with
a marvelous vigor and with that conquering ambition which Vico called
_mens heroica_. Nevertheless. Voltaire's signal characteristic was his
lucidity, his negative lucidity.

There was a great and free intellectual movement in England in the
eighteenth century--indeed, it was from England that it passed into
France; but the English had not that strong natural bent for lucidity
which the French had. Its bent was toward other things in preference.
Our leading thinkers had not the genius and passion for lucidity which
distinguished Voltaire. In their free inquiry they soon found themselves
coming into collision with a number of established facts, beliefs,
conventions. Thereupon all sorts of practical considerations began to
sway them. The danger signal went up, they often stopped short, turned
their eyes another way, or drew down a curtain between themselves and
the light. "It seems highly probable," said Voltaire, "that nature has
made thinking a portion of the brain, as vegetation is a function of
trees; that we think by the brain just as we walk by the feet." So our
reason, at least, would lead us to conclude, if the theologians did not
assure us of the contrary; such, too, was the opinion of Locke, but he
did not venture to announce it. The French Revolution came, England grew
to abhor France, and was cut off from the Continent, did great things,
gained much, but not in lucidity. The Continent was reopened, the
century advanced, time and experience brought their lessons, lovers of
free and clear thought, such as the late John Stuart Mill, arose among
us. But we could not say that they had by any means founded among us the
reign of lucidity.

Let them consider that movement of which we were hearing so much just
now: let them look at the Salvation Army and its operations. They would
see numbers, funds, energy, devotedness, excitement, conversions, and
a total absence of lucidity. A little lucidity would make the whole
movement impossible. That movement took for granted as its basis what
was no longer possible or receivable; its adherents proceeded in all
they did on the assumption that that basis was perfectly solid, and
neither saw that it was not solid, nor ever even thought of asking
themselves whether it was solid or not.

Taking a very different movement, and one of far higher dignity and
import, they had all had before their minds lately the long-devoted,
laborious, influential, pure, pathetic life of Dr. Pusey, which had just
ended. Many of them had also been reading in the lively volumes of that
acute, but not always good-natured rattle, Mr. Mozley, an account of
that great movement which took from Dr. Pusey its earlier name. Of its
later stage of Ritualism they had had in this country a now celebrated
experience. This movement was full of interest. It had produced men to
be respected, men to be admired, men to be beloved, men of learning,
goodness, genius, and charm. But could they resist the truth that
lucidity would have been fatal to it? The movers of all those questions
about apostolical succession, church patristic authority, primitive
usage, postures, vestments--questions so passionately debated, and on
which he would not seek to cast ridicule--did not they all begin by
taking for granted something no longer possible or receivable, build on
this basis as if it were indubitably solid, and fail to see that their
basis not being solid, all they built upon it was fantastic?

He would not say that negative lucidity was in itself a satisfactory
possession, but he said that it was inevitable and indispensable, and
that it was the condition of all serious construction for the future.
Without it at present a man or a nation was intellectually and
spiritually all abroad. If they saw it accompanied in France by much
that they shrank from, they should reflect that in England it would
have influences joined with it which it had not in France--the natural
seriousness of the people, their sense of reverence and respect, their
love for the past. Come it must; and here where it had been so late in
coming, it would probably be for the first time seen to come without
danger.

Capitals were natural centers of mental movement, and it was natural for
the classes with most leisure, most freedom, most means of cultivation,
and most conversance with the wide world to have lucidity though often
they had it not. To generate a spirit of lucidity in provincial towns,
and among the middle classes bound to a life of much routine and plunged
in business, was more difficult. Schools and universities, with serious
and disinterested studies, and connecting those studies the one with the
other and continuing them into years of manhood, were in this case the
best agency they could use. It might be slow, but it was sure. Such
an agency they were now going to employ. Might it fulfill all their
expectations! Might their students, in the words quoted just now,
advance in every direction with a marvelous vigor, and with that
conquering ambition which Vico called _mens heroica_! And among the many
good results of this, might one result be the acquisition in their midst
of that indispensable spirit--the spirit of lucidity!

* * * * *

ON SOME APPARATUS THAT PERMIT OF ENTERING FLAMES.

[Footnote: A. de Rochas in the _Revue Scientifique_.]

In the following notes I shall recall a few experiments that indicate
under what conditions the human organism is permitted to remain unharmed
amid flames. These experiments were published in England in 1882, in the
twelfth letter from Brewster to Walter Scott on natural magic. They are,
I believe, not much known in France, and possess a practical interest
for those who are engaged in the art of combating fires.

At the end of the last century Humphry Davy observed that, on placing a
very fine wire gauze over a flame, the latter was cooled to such a
point that it could not traverse the meshes. This phenomenon, which he
attributed to the conductivity and radiating power of the metal, he soon
utilized in the construction of a lamp for miners.

Some years afterward Chevalier Aldini, of Milan, conceived the idea of
making a new application of Davy's discovery in the manufacture of an
envelope that should permit a man to enter into the midst of flames.
This envelope, which was made of metallic gauze with 1-25th of an inch
meshes, was composed of five pieces, as follows: (1) a helmet, with
mask, large enough, to allow a certain space between it and the internal
bonnet of which I shall speak; (2) a cuirass with armlets; (3) a skirt
for the lower part of the belly and the thighs; (4) a pair of boots
formed of a double wire gauze; and (5) a shield five feet long by one
and a half wide, formed of metallic gauze stretched over a light iron
frame. Beneath this armor the experimenter was clad in breeches and a
close coat of coarse cloth that had previously been soaked in a solution
of alum. The head, hands, and feet were covered by envelopes of asbestos
cloth whose fibers were about a half millimeter in diameter. The bonnet
contained apertures for the eyes, nose, and ears, and consisted of a
single thickness of fabric, as did the stockings, but the gloves were of
double thickness, so that the wearer could seize burning objects with
the hands.

Aldini, convinced of the services that his apparatus might render to
humanity, traveled over Europe and gave gratuitous representations with
it. The exercises generally took place in the following order: Aldini
began by first wrapping his finger in asbestos and then with a double
layer of wire gauze. He then held it for some instants in the flame of
a candle or alcohol lamp. One of his assistants afterward put on the
asbestos glove of which I have spoken, and, protecting the palm of his
hand with another piece of asbestos cloth, seized a piece of red-hot
iron from a furnace and slowly carried it to a distance of forty or
fifty meters, lighted some straw with it, and then carried it back to
the furnace. On other occasions, the experimenters, holding firebrands
in their hands, walked for five minutes over a large grating under which
fagots were burning.

In order to show how the head, eyes, and lungs were protected by the
wire gauze apparatus, one of the experimenters put on the asbestos
bonnet, helmet, and cuirass, and fixed the shield in front of his
breast. Then, in a chafing dish placed on a level with his shoulder, a
great fire of shavings was lighted, and care was taken to keep it up.
Into the midst of these flames the experimenter then plunged his head
and remained thus five or six minutes with his face turned toward them.
In an exhibition given at Paris before a committee from the Academic
des Sciences, there were set up two parallel fences formed of straw,
connected by iron wire to light wicker work, and arranged so as to leave
between them a passage 3 feet wide by 30 long. The heat was so intense,
when the fences were set on fire, that no one could approach nearer than
20 or 25 feet; and the flames seemed to fill the whole space between
them, and rose to a height of 9 or 10 feet. Six men clad in the Aldini
suit went in, one behind the other, between the blazing fences, and
walked slowly backward and forward in the narrow passage, while the fire
was being fed with fresh combustibles from the exterior. One of these
men carried on his back, in an ozier basket covered with wire gauze, a
child eight years of age, who had on no other clothing than an asbestos
bonnet. This same man, having the child with him, entered on another
occasion a clear fire whose flames reached a height of 18 feet, and
whose intensity was such that it could not be looked at. He remained
therein so long that the spectators began to fear that he had succumbed;
but he finally came out safe and sound.

One of the conclusions to be drawn from the facts just stated is that
man can breathe in the midst of flames. This marvelous property cannot
be attributed exclusively to the cooling of the air by its passage
through the gauze before reaching the lungs; it shows also a very great
resistance of our organs to the action of heat. The following, moreover,
are direct proofs of such resistance. In England, in their first
experiment, Messrs. Joseph Banks, Charles Blagden, and Dr. Solander
remained for ten minutes in a hot-house whose temperature was 211 deg.
Fahr., and their bodies preserved therein very nearly the usual heat. On
breathing against a thermometer they caused the mercury to fall several
degrees. Each expiration, especially when it was somewhat strong,
produced in their nostrils an agreeable impression of coolness, and the
same impression was also produced on their fingers when breathed upon.
When they touched themselves their skin seemed to be as cold as that of
a corpse; but contact with their watch chains caused them to experience
a sensation like that of a burn. A thermometer placed under the tongue
of one of the experimenters marked 98 deg. Fahr., which is the normal
temperature of the human species.

Emboldened by these first results, Blagden entered a hot-house in which
the thermometer in certain parts reached 262 deg. Fahr. He remained therein
eight minutes, walked about in all directions, and stopped in the
coolest part, which was at 240 deg. Fahr. During all this time he
experienced no painful sensations; but, at the end of seven minutes, he
felt an oppression of the lungs that inquieted him and caused him to
leave the place. His pulse at that moment showed 144 beats to the
minute, that is to say, double what it usually did. To ascertain whether
there was any error in the indications of the thermometer, and to find
out what effect would take place on inert substances exposed to the hot
air that he had breathed, Blogden placed some eggs in a zinc plate in
the hot-house, alongside the thermometer, and found that in twenty
minutes they were baked hard.

A case is reported where workmen entered a furnace for drying moulds, in
England, the temperature of which was 177 deg., and whose iron sole plate
was so hot that it carbonized their wooden shoes. In the immediate
vicinity of this furnace the temperature rose to 160 deg.. Persons not of
the trade who approached anywhere near the furnace experienced pain in
the eyes, nose, and ears.

A baker is cited in Angoumois, France, who spent ten minutes in a
furnace at 132 deg. C.

The resistance of the human organism to so high temperatures can be
attributed to several causes. First, it has been found that the quantity
of carbonic acid exhaled by the lungs, and consequently the chemical
phenomena of internal combustion that are a source of animal heat,
diminish in measure as the external temperature rises. Hence, a conflict
which has for result the retardation of the moment at which a living
being will tend, without obstacle, to take the temperature of the
surrounding medium. On another hand, it has been observed that man
resists heat so much the less in proportion as the air is saturated
with vapors. Dr. Berger, who supported for seven minutes a temperature
varying from 109 deg. to 110 deg. C. in dry air, could remain only twelve
minutes in a bagnio whose temperature rose from 41 deg. to 51.75 deg.. At the
Hammam of Paris the highest temperature obtained is 87 deg., and Dr. E.
Martin has not been able to remain therein more than five minutes. This
physician reports that in 1743, the thermometer having exceeded 40 deg. at
Pekin, 14,000 persons perished. These facts are explained by the cooling
that the evaporation of perspiration produces on the surface of the
body. Edwards has calculated that such evaporation is ten times greater
in dry air in motion than in calm and humid air. The observations become
still more striking when the skin is put in contact with a liquid or a
solid which suppresses perspiration. Lemoine endured a bath of Bareges
water of 37 deg. for half an hour; but at 45 deg. he could not remain in it more
than seven minutes, and the perspiration began to flow at the end of six
minutes. According to Brewster, persons who experience no malaise near
a fire which communicates a temperature of 100 deg. C. to them, can hardly
bear contact with alcohol and oil at 55 deg. and mercury at 48 deg..

The facts adduced permit us to understand how it was possible to bear
one of the proofs to which it is said those were submitted who wished
to be initiated into the Egyptian mysteries. In a vast vaulted chamber
nearly a hundred feet long, there were erected two fences formed of
posts, around which were wound branches of Arabian balm, Egyptian thorn,
and tamarind--all very flexible and inflammable woods. When this was set
on fire the flames arose as far as the vault, licked it, and gave the
chamber the appearance of a hot furnace, the smoke escaping through
pipes made for the purpose. Then the door was suddenly opened before the
neophyte, and he was ordered to traverse this burning place, whose floor
was composed of an incandescent grating.

The Abbe Terrason recounts all these details in his historic romance
"Sethos," printed at the end of last century. Unfortunately literary
frauds were in fashion then, and the book, published as a translation of
an old Greek manuscript, gives no indication of sources. I have sought
in special works for the data which the abbe must have had as a basis,
but I have not been able to find them. I suppose, however, that
this description, which is so precise, is not merely a work of the
imagination. The author goes so far as to give the dimensions of the
grating (30 feet by 8), and, greatly embarrassed to explain how his hero
was enabled to traverse it without being burned, is obliged to suppose
it to have been formed of very thick bars, between which Sethos had care
to place his feet. But this explanation is inadmissible. He who had the
courage to rush, head bowed, into the midst of the flames, certainly
would not have amused himself by choosing the place to put his feet.
Braving the fire that surrounded his entire body, he must have had no
other thought than that of reaching the end of his dangerous voyage as
soon as possible. We cannot see very well, moreover, how this immense
grate, lying on the ground, was raised to a red heat and kept at such a
temperature. It is infinitely more simple to suppose that between the
two fences there was a ditch sufficiently deep in which a fire had
also been lighted, and which was covered by a grating as in the Aldini
experiments. It is even probable that this grating was of copper,
which, illuminated by the fireplace, must have presented a terrifying
brilliancy, while in reality it served only to prevent the flames from
the fireplace reaching him who dared to brave them.

* * * * *

THE BUILDING STONE SUPPLY.

The use of stone as a building material was not resorted to, except to
a trifling extent, in this country until long after the need of such a
solid substance was felt. The early settler contented himself with the
log cabin, the corduroy road, and the wooden bridge, and loose stone
enough for foundation purposes could readily be gathered from the
surface of the earth. Even after the desirability of more handsome and
durable building material for public edifices in the colonial cities
than wood became apparent, the ample resources which nature had afforded
in this country were overlooked, and brick and stone were imported by
the Dutch and English settlers from the Old World. Thus we find the
colonists of the New Netherlands putting yellow brick on their list
of non-dutiable imports in 1648; and such buildings in Boston as are
described as being "fairly set forth with brick, tile, slate, and
stone," were thus provided only with foreign products. Isolated
instances of quarrying stone are known to have occurred in the last
century; but they are rare. The edifice known as "King's Chapel,"
Boston, erected in 1752, is the first one on record as being built from
American stone; this was granite, brought from Braintree, Mass.

Granite is a rock particularly abundant in New England, though also
found in lesser quantities elsewhere in this country. The first granite
quarries that were extensively developed were those at Quincy, Mass.,
and work began at that point early in the present century. The fame of
the stone became widespread, and it was sent to distant markets--even to
New Orleans. The old Merchants' Exchange in New York (afterward used as
a custom house) the Astor House in that city, and the Custom House in
New Orleans, all nearly or quite fifty years old, were constructed of
Quincy granite, as were many other fine buildings along the Atlantic
coast. In later years, not only isolated public edifices, but also whole
blocks of stores, have been constructed of this material. It was from
the Quincy quarries that the first railroad in this country was built;
this was a horse-railroad, three miles long, extending to Neponset
River, built in 1827.

Other points in Massachusetts have been famed for their excellent
granite. After Maine was set off as a distinct State, Fox Island
acquired repute for its granite, and built up an extensive traffic
therein. Westerly, R.I., has also been engaged in quarrying this
valuable rock for many years, most of its choicer specimens having been
wrought for monumental purposes. Statues and other elaborate monumental
designs are now extensively made therefrom. Smaller pieces and a coarser
quality of the stone are here and elsewhere along the coast obtained in
large quantities for the construction of massive breakwaters to protect
harbors. Another point famous for its granite is Staten Island, New
York. This stone weighs 180 pounds to the cubic foot, while the Quincy
granite weighs but 165. The Staten Island product is used not only for
building purposes, but is also especially esteemed for paving after both
the Russ and Belgian patents. New York and other cities derive large
supplies from this source. The granite of Weehawken, N.J., is of the
same character, and greatly in demand. Port Deposit, Md., and Richmond,
Va, are also centers of granite production. Near Abbeville, S.C., and
in Georgia, granite is found quite like that of Quincy. Much southern
granite, however, decomposes readily, and is almost as soft as clay.
This variety of stone is found in great abundance in the Rocky
Mountains; but, except to a slight extent in California, it is not yet
quarried there.

Granite, having little grain, can be cut into blocks of almost any size
and shape. Specimens as much as eighty feet long have been taken out and
transported great distances. The quarrying is done by drilling a series
of small holes, six inches or more deep and almost the same distance
apart, inserting steel wedges along the whole line and then tapping each
gently with a hammer in succession, in order that the strain may be
evenly distributed.

A building material that came into use earlier than granite is known as
freestone or sandstone; although its first employment does not date back
further than the erection of King's Chapel, Boston, already referred to
as the earliest well-known occasion where granite was used in building.
Altogether the most famous American sandstone quarries are those at
Portland, on the Connecticut River, opposite Middletown. These were
worked before the Revolution; and their product has been shipped to many
distant points in the country. The long rows of "brownstone fronts" in
New York city are mostly of Portland stone, though in many cases the
walls are chiefly of brick covered with thin layers of the stone. The
old red sandstone of the Connecticut valley is distinguished in geology
for the discovery of gigantic fossil footprints of birds, first noticed
in the Portland quarries in 1802. Some of these footprints measured
ten to sixteen inches, and they were from four to six feet apart. The
sandstone of Belleville, N.J., has also extensive use and reputation.
Trinity Church in New York city and the Boston Atheneum are built of the
product of these quarries; St. Lawrence County, New York, is noted also
for a fine bed of sandstone. At Potsdam it is exposed to a depth of
seventy feet. There are places though, in New England, New York, and
Eastern Pennsylvania, where a depth of three hundred feet has been
reached. The Potsdam sandstone is often split to the thinness of an
inch. It hardens by exposure, and is often used for smelting furnace
hearth-stones. Shawangunk Mountain, in Ulster County, yields a sandstone
of inferior quality, which has been unsuccessfully tried for paving;
as it wears very unevenly. From Ulster, Greene, and Albany Counties
sandstone slabs for sidewalks are extensively quarried for city use;
the principal outlets of these sections being Kingston, Saugerties,
Coxsackie, Bristol, and New Baltimore, on the Hudson. In this region
quantities amounting to millions of square feet are taken out in large
sheets, which are often sawed into the sizes desired. The vicinity of
Medina, in Western New York, yields a sandstone extensively used in that
section for paving and curbing, and a little for building. A rather poor
quality of this stone has been found along the Potomac, and some of it
was used in the erection of the old Capitol building at Washington.
Ohio yields a sandstone that is of a light gray color; Berea, Amherst,
Vermilion, and Massillon are the chief points of production. St.
Genevieve, Mo., yields a stone of fine grain of a light straw color,
which is quite equal to the famous Caen stone of France. The Lake
Superior sandstones are dark and coarse grained, but strong.

In some parts of the country, where neither granite nor sandstone
is easily procured, blue and gray limestone are sometimes used for
building, and, when hammer dressed, often look like granite. A serious
objection to their use, however, is the occasional presence of iron,
which rusts on exposure, and defaces the building. In Western New York
they are widely used. Topeka stone, like the coquine of Florida and
Bermuda, is soft like wood when first quarried, and easily wrought,
but it hardens on exposure. The limestones of Canton, Mo., Joliet and
Athens, Ill., Dayton, Sandusky, Marblehead, and other points in Ohio,
Ellittsville, Ind., and Louisville and Bowling Green, Ky., are great
favorites west. In many of these regions limestone is extensively used
for macadamizing roads, for which it is excellently adapted. It also
yields excellent slabs or flags for sidewalks.

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