tained
a small quantity of strongly aromatic crystalline body, volatile,
burning easily with a smoky flame, and melting at about 50°C.
Unfortunately the quantity obtained was too small to admit of a full
investigation of its composition and properties. He suggested that
perhaps the diamond was formed from hydrocarbon simultaneously with
this aromatic body. Prof. H. Carvill Lewis, at the meeting of the
British Association at Birmingham, in September, 1886, in a paper "On
the Genesis of the Dia-mond," stated that from the Do, Beers' Mine, in
South Africa, at a depth of 600 feet, there had been sent him specimens
of unaltered rock which proved to be peridotite containing
carbonaceous shale. He added that information received from New South
Wales, Borneo, and Brazil led him to believe all diamonds to be the
result of the intrusion of a peridotite through carbon-/ aceous rocks
and coal seams. The similarity of the South African peridotite to that
described by Joseph S. Diller in Kentucky led Professor Lewis to
suggest interesting possibilities as to the occurrence of diamonds
there ; and on the invitation of Prof. John R. Proctor, State Geologist
of Kentucky, in the summer of 1887, Mr. Diller and the writer were
sent, by Major John W. Powell, t-he Director of the United States
Geological Survey, to make an investigation. The locality is easily
reached by way of the East Kentucky Railroad, which ends in Carter
County, at Willard, where conveyances may be obtained of the farmers
for the remaining ten miles. The best exposures of the peridotite occur
along Ison's Creek, in Elliott County. The peridotite alters and
disintegrates readily, but because the declivity of the surface here is
considerable, the transportation of material almost keeps pace with
disintegration, and there is no great accumulation of residuary
deposits upon the narrow divides and hillsides. The specific gravity
and durability of the gems found in connection with peridotite are
generally greater than of serpentine and other products of its
alteration. On this account they accumulate upon the surface, and in
favorable positions along adjacent lines of drainage. The plan followed
was to search by sifting and carefully panning the beds, receiving the
drainage directly from the surface of the peridotite, and to enlist the
services of the people
» Am. J. Sci. III., Vol. 32, p. 121, Aug., 1886.
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