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AND UNDER GREAT PRESSURES
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discharge in high vacua, and appeared to him to behave in a similar manner to diamond powder.
Tests of specific gravity by immersion of the particles in borotungstate of cadmium and iodide of methylene gave a density of 3-3 to 3-5.
The particles appeared to consist of two kinds—one, irregular opaque black particles; the other, translucent plates resembling flakes of mica, generally of square or irregular shape.
When placed in a cell in iodide of methylene and projected by an electric lantern on the screen, they were clearly seen—the plates appeared to be about 1/500 inch in length and of extreme thinness.
On subjecting the powder to the blowpipe all hard particles disappeared, leaving a yellowish-grey residue, but it should be stated that the powder was not previously levigated to remove the lighter portions, which would account for the residue.
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