284- Dr. Hare on Fused Carbon, 



which I have made in reply to that memoir to appear before 

 the public in the same channel. I inclose in this letter a copy 

 of them. I am, gentlemen, respectfully yours, &c. 



Philadelphia, March 15, 1825. RoBERT Hare. 



Professor Silliman, about two years ago, published an ac- 

 count of some phaenomena observed during the ignition of 

 pieces of charcoal by a galvanic deflagrator, the poles of which 

 they had been severally employed to terminate. On the char- 

 coal attached to the positive pole a projection was observed 

 to ensue — in the other, a corresponding concavity. The pro- 

 jection he supposed to consist of carbon, fused, volatilized, and 

 transferi'ed from the charcoal of the opposite pole, where the 

 concavity was discovered. 



In a late number of the Journal of the Academy of Natural 

 Sciences of Philadelphia, Mr. Lardner Vanuxem communi- 

 cates his observations on a supposed specimen of fused char- 

 coal, sent to Professor Cooper by Dr. Macneven of New York, 

 which appears to have been iron — and the author appears to 

 have received, and evidently intends to convey, the impression, 

 that the substances considered as fused or volatilized carbon 

 by Professor Silliman must have been similarly constituted. 



Mr. Vanuxem, speaking of the mass which he has exa- 

 mined, informs us, that — " It consisted of one large and one 

 small globule, connected together by a thread, or thin bar, of 

 the same material, and resembled a double-headed shot." 



And again he says: — " It was then put into an agate mor- 

 tar, pressed and struck with considerable force — finding it 

 yielded without bieaking, and observing that it received a po- 

 lish, it was examined and found to resemble iron. To con- 

 firm the analogy, it was next tried with a file, which acted 

 upon it as it would on soft steel or iron — after this it was sub- 

 jected to a magnet, to which it readily attached itself — and 

 lastly, with a hammer : by its great malleability, conjoined with 

 the characters just mentioned, it proved its identity with iron." 



He moreover states, that the substance in question was at- 

 tacked by nitric acid, and afterwards was chiefly taken up by 

 muriatic acid, whence an hydratcd peroxide of iron was pre- 

 cipitated by ammonia. 



On reading this account o{' the substance examined by 

 Mr. Vanuxem, it was evident to me that it had not the slightest 

 resemblance to those which Professor Silliman had described 

 as fused carbon. A product which I had myself obtained, 

 and which corresponded perfectly with his description, had 

 been preserved in a glass tube. This substance crumbled 

 when subjected to pressure — acquired no polish by hammering 



or 



