Richmond dispatch. [volume] (Richmond, Va.) 1884-1903, 1899-05-31


well-knoWn ochreous aspect Essentially
the same material Is, however, now eX-
cavated at a depth OF close upon TWO
thousand feet as was struck by the first
prOspector's pickaxe thirty years ago.
The mines, unless all the indications at
| hand prove deceptive, are bottomless.
Their precious contents, instead OF peter
ing out" with descent. grow more album
dant. They were supplied, perhaps, by
I direct communication with reservoirs 80
| profoundly subterranean as 10 be aces
| sble only to those personally conducted
| by Virgil or Jules Verne. II appears GER
tain moreover. that each pipe was fed
from an independent source. Their pro-
ducts are separately recognizable A
trained eye can distinguish DE Beers from
Kaffeefontein diamonds; those dug within
the range of a rifle bullet at Bullfontein
and Dutoitspan show a discernible diff
ference of color; the perfect octahedrons
Of Newlands resemble neither the irreg-
ular white stones from Wesselton nor
the "cross- grained" frosted" stones from
Leicester while the Jagersfontein gems
remind connoisseurs by their steely gilt
ter of the old Indian "blues'-the or
loff,'' the Regent" the 'Sancy' and
fetch proportionately high prices.
MAKING CARBON VAPoRIzE.
Our readers do not need to be told that
diamonds are composed OF pure carbon.
Hence. alone among gems, spurious or
true, they are perfectly transparent 10
the Rontgen rays Silica, the usual sub
stratum of jewels, glass. paste, crystal,
are all comparatively Opaque. An easy
and infallibe test for genuine diamonds
has thus been unexpectedly provided by
the Wurzburg professors memorable dis
covery.
Carbon Is an emnently lntractable sub
stance. At ordinary temperatures no SOL
vent can be found for IT, At no tempera-
ture, unless by extraordinary compulsion,
will it consent to melt. In the electric
arc it passes directly into yapor, skipping
the intermediate state
The key to the enigma of diamond pro-
duction should accordingly be found IN
the lquefaction Of carbon. The circum-
stances under which IL is accomplished
can hardly be other than identical with
those attending the development or the
precious stones Now. IL is possible TO de-
termine approximately, by calculations
based on the analogy Of other substances
the nature OF those circumstances. This
has been done by Professor Dewar. He
finds the boiling point of carbon to be
3.S4 centigrade degrees above the "abso-
lutte zero" equivalent to $500 degrees on
In the neighbOrhood OF $500 degrees (ab-
solute) and the corresponding critical
pressure" scarcely, If at all, falls short OF
fifteen tons to the square inch.
CARBON DISSOLVED IN IRON.
That fused iron dlssolves carbon Is no
recent discovery, but the affinity, illus
trated in the Bessemer process. has been
widely developed and investigated by NJ.
MOissan. At the temperature OF the cleo
trio furnace he finds this ordinarily In
tractable substance to be freely soluble
in aluminium. chromium, manganese,
nickel. uranium-above all. in boiling sill
yer and iron. Unluckily, it separates from
them In cooling. as II IL deposited after
subllmation, not I'm the radiant crystalline
form. but merely in dull fakes OF graph
lite. Only by main force can the desired
substitution of the one for the other be
effected. 1t would seem that the intimate
marshalling power in this kind OF matter
is virtually annulled by a trifilng sepa-
ration of the centres from which IL ema-
mates. IL acts only when they are brought
within striking distance by mechanical
means. The difficulty thus raised Is for
midable: yet IL must be overcome before
the manufacture of the gems enters upon
a practical stage. NJ. Moissan was the
first duly 10 estimate and successfully TO
cope with IT, His experiments were
grounded upon careful inquiry into South
African mining conditions. That they dis
close great profundity OF origin for the
excavated objects was at once apparent
to him, and underground factories, II
placed deep enough. can avail to an al
most unlimited extent OF geocentric heat
and geogonic pressure. The crux was 10 |
produce the same results without the |
same facilities. Sufficient heat was m
deed at hand; the needful pressure was
less easily evoked. But here a certain
anomaly in the behavior OF cooling iron
came 10 the rescue. Pure iron follows the |
common rule OF contraction In solidlfying:
but iron saturated with carbon expands.
after the manner OF water turning into
ice. Silver shows the same popularity.
Now. by suddenly refrigerating q mass OF |
iron. hard superficial shell |
would obviously be formed. powerfully |
the interior. and hindering |
its natural expansion. Frost-burst water |
pipes bat too Familiarity exemplify the all |
but irresistible strength OF the moecu- |
lar effort TO get room under analogous |
circumstances. The tremendous interior |
pressure created by the restraint imposed |
upon II In NJ. Moissans crucibles sufGces |
10 liquefy the carbon contained in them, |
and capitalization ensues.
That stores Of native Iron exist deep /