The Russellville Democrat., 1880-04-22
MR. HANNAY'S DIAMONDS.
Genuine, But 1t Takes 1000 to Make a salab1e Stone.
 London Standard.

London Standard.
 The announcement that Mir. Ballantine Hannay, of Glasgow, would describe his process of producing diamonds atifi- ciaIly, attracted an unusually large gath ering to the weekly meeting of the Royal Society last night. Mir. Hannay was not however, present, and the papers were read by one of the secretaries. The sec ord paper, which occupied only few minutes in reading, was Preliminary Note on the Artificial Formation of Dia- monds." by MT. Hannay. The author mentioned that he had conceived that as gases under great pressure and at high temperature dissolved solids, which after wards crystallized out on the heat and pressure being removed, possibly water gas-or gas passing from the liquid into the gaseous condition-might act thus on carbon, which might subsequently crys- tallize in the form of diamonds. In this expectation he was disappointed. All forms of carbon, charcoal, lampblack, graphite, etc., refused to dissolve under the condition presented to them: After many failures he was recommended by Prof. Stokes to take advantage of the ob- servations of Messrs. Lieving and Dewar on the affinity of hydrogen for certain metals, and by this agency to dissociate the hydrogen from the carbon in the va rious hydrocarbons. He claimed to have eventually succeeded by submitting "a hydrocarbon" in the presence of ca nitrogenous compound" to immense pressure and heat, with the result that on breaking open the iron tubes in which the experiments were performed, minute crystals of diamonds, or in other words, crystallized carbon, were found to have been deposited as the residuum. The paper was criticised by several of the Fellows. No doubt was expressed as to the perfect good faith of MT. Han nay. At the same time the attitude of the meeting was one of scientific skepti- cism-taking the term in perfectly in- offensive meaning-until further infor- nation was afforded it. This Mr. Han- nay promised to supply at an early date, and to perform the experiments, if need be, before the society or committee ap- pointed by it. Meantime the great trou- ble he had was to find vessels in which to make the experiment strong enough to bear the prodiglous pressure they are subjected to. It also transpired that Mir. Hanney held out no hopes of his experi- ments ever being commercially valuable. At present the cost of making about 5 shillings' worth of the meanest stones exhibited being something like $5. It is, therefore, only rich people who can afford the pastime of diamond making. Prof Story y-Maskelyne expressed his firm belief in the good faith of his cor respondent. The stones satisfied every test applicable to the native diamond, and these tests having been repeated by Prof. Roscoe, of Manchester, that gentle man expressed an equally confident opinion as to their being genuine dia- monds The main doubt as to their be- ing genuine which still fingered about Prof. Maskelyne's mind was the fact that the stones sent to him were exceedingly minute-none over the 128th of a carat in weight, and therefore all but micros- copical. He could not see single entire crystal. All the fragments seemed as if they were broken bits of larger dia- monds, and one of the largest fragments more especially bore this character. The fact of their being broken Mir. Hannay attributed to the mechanical violence which they underwent on the heavy iron tubes in which they were crystal lized being broken to get them out Finally, Prof. Maskelyne, though at pres ent considering the discovery at best merely of scientific interest, was not al- together certain that now that the prin- ciple has been struck on, larger stones might not eventually be produced. The stones exhibited filled glass tube not much bigger than a quill, and were so small that, as Prof Maskelyne remarked, it would take about a thousand of them to make up the bulk of the smallest marketable diamond