1896.] MICROSCOPICAL JOURNAL. 303 



dust of silicic carbide, as produced by the electrical des- 

 truction of artificially prepared carbon rods, and when 

 by its application, I became enabled to donainate every 

 hard substance in nature, with the exception of the dia- 

 mond itself, I deemed my experiences as of such a novel 

 character and of sufficient general interest to communicate 

 them, for the benefit of all who are interested in the mic- 

 roscopic study of Mineralogy. 



During a collateral study of a pseudo-meteoric iron. I 

 was enabled to make some interesting studies of both 

 black and white diamond, by fracturing, and by polariz- 

 ation, and otherwise, the results of which study present 

 much of microscopic interest, not hitherto published in 

 our Journals devoted to microscopic science; and in con- 

 nection with the subject of rock study, I might relate 

 that while in Amsterdam, Holland, in the summer of 

 1887, I paid a florin for a half carat of diamond dust, while 

 visiting the largest diamond cutting house in that city. 

 The proprietor also brought me a 62 carat diamond just 

 finished by them and laughingly remarked that he would 

 sell it to Mr. Grould of the U. S., when I pleasantly re- 

 torted, that we called him "Jay Gould." I carried the 

 sample of diamond dust in my pocket book for five years 

 expecting to be able to use it at some future time and 

 finally, when I became actively engaged in the study of 

 the structure of the real diamond, the long preserved 

 diamond dust could not be found, but with "Silicon Car- 

 bide" available everywhere, diamond dust will not possess 

 the same interest as it formerly did for abrading or cut- 

 ting purposes. 



In conclusion, the requisites for the analytical adapta- 

 tion of the tacts already enlarged upon herein, are rela- 

 tively few and inexpensive, as a fragment of a common 

 half inch thick emery wheel, having a surface allowing 

 an oval sweep of five or six inches, a few pieces of com- 



