The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1896-10-31
MOISSAN MADE DIAMONDS
With His Electric Furnace Before a
New York Audience.

SILICA VolatiIized Into Violet Gas-Bril-
liant Demonstration by the Distin-
guished French Chemist at the College
of Physicians and Surgeons.
Before an sppreciative audience that
completely filed the large lecture room
of the College of Physicians and Sur
geons NJ. Henri Mnissan of the Institute
of France and of the Academic des
Sciences, who is known throughout the
world for his chemical Investigations
with very high temperatures ana his re-
searches into the nature and applications
of the oarbides, delivered lecture Tues
day night on the uses of the electric fur
mace and the results obtained by it. &C
oompanied by some brilliant experiments,
says the New York Sun. The audience
consisted chiefly of persons interested in
chemistry. students. professors. cleo
tricians, and engineers, with n sprink-
ling of ladies. and followed the speaker
with close attention during the hour and
half that the lecture lasted. Nj. MoissRn
spoke in French, and while some of his
hearers understood his words, the rest
understood the chemical points he WAS
expounding.
NJ. Moissan is a man of about forty -fvo
yeare, of medium height and slender
build. His fare is striking one, his
hair and beard are jet black. streaked
with gray, and his smile is very PLEASANT
He spoke easily and unaffectedly. in
clear, melodious voice.
He explained that while the carbon
compounds have been studied with great
care By organic chemists during the past
fifty years. the study of the different
stages through which carbon passes had
been comparatively neglected. In his
endeavor to obtain pure carbon, the
containing from 10 to Is per cent. of
impurities, he had found it necessary to
use very high temperatures and had suo-
ceeded in obtaining one form OF pure car
bon, graphite. High temperature alone,
however, would not yield the crystalized
form of carbon, diamond. He set to
work to find out the composition of
diamonds by reducing some to ashes. In
all, whether they came from the Cape of
Good Hope or from Brazil, he found
iron, save in one very pure green hard
stone from Brazil. By the study of the
nature of the ground and of the geologi-
sal formation In which Cape diamonds
are found, he found that the earth, be-
sides graphite and microscopic dia-
monds, always contained granite.
Granite Is the product of great pressure
ami this fact led him to the idea that
diamonds might also be obtained by
pressure AS cast iron increases in vol
ume in passing from the liquid to the
solid state, he WAS led to believe that if
an element of carbon were enclosed in
a globule of cast iron that was cooling
it would be subjected to the requisite
pressure.
In order to obtain heat sufficiently
great and at the same time to be able
to measure it, he devised the simple form
of electric furnace with which the ex-
pertinent last evening was performed. 1t
consists of two clay bricks, the lower
one about elghtetn inches square and a
foot deep, the upper one about six inches
deep. In the lower one is followed out
an elliptical hole TO contain the orucible,
while two carbon electrodes pass from the
cavity to the exterior, where they are
connected with tho electrical battery.
The upper brick serves for a cover. M.
Moissan first sprinkled the cavity with
magnesia in order to prevent the forma-
ton OF calcium carbide. He then
placed il in the crucible, into which he
had put soft iron fir g and charcoal,