Morning journal and courier., 1880-03-18
Mr. Hannay's Diamonds.
Genuine, Bnt 1t Takes LOGO to Make a
 Salable Stone.


 From the London standard.]
 The announcement that MT. Ballantine Hannay, of Glasgow, would describe his pro cess of producing diamonds artifcially, at tracted an unusually large gathering to the weekly meeting of the Royal Society last night. MT. Hannay was not, however, pres ent, and the papers were read by one of the secretaries. The second paper, which occu pied only few minutes in reading, was 8 Preliminary Note on the Artificial Formation of Diamonds" by Mir. Hannay. The author mentioned that he had conceived that as gases under great pressure and at high temperature dissolved solids. which afterwards 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 crystalline in the form of diamonds. In this expectation he was disappointed. All forms of carbon, charcoal, lamp black, graphite, etc, refused to dissolve under the conditlou presented to them. After many failures he was recommended by Professor Stokes to take advantage of the observations of Messrs Lieving and Dewar on the affinity of hydro gen for certain metalz, and by this agency to dissociate the hydrogen from the carbon in the various hydro cartoons. He claimed to have eventually succeeded by submitting "a hydro carbon" in the presence of "a nitrogen ous 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 Tn other words crystalliZed carbon, were found to have been deposited as the residuum. The paper was criticised by several Fellows Nu doubt was expressed as to the perfect good faith of Mir. Hannay. At the same time the attitude of the meeting was one of scientific skepticism-taking the term in perfectly in offensive meauing-until further information was afforded it. This Mir. Hannay promised to supply st an early date, and to perform the experiments if need be before the society or committee appointed by 1t. Meantime the great trouble he had was to find vessels ill which to make the experiment strong enough to bear the prodigious pressure they were sub iected to. It also transpired that MT. Hannay held out no hopes of his experiments ever be- ing commercially valuable; at present the cost of making about shillings worth of the meanest stones exhibited being something like 95. It is, therefore, only rich people who can afford the pastime of diamond making. Professor Story-Maskelyne expressed his firm belief in the good faith of his core spondent. The stones satisfied every test ap- plicable to the native diamond and these tests having been repeated by Professor Roscoe, of Manchester, that gentleman expressed an equally confident opinion as to their being genuine diamonds. The main doubt as to their being genuine which still fingered about Professor Maskelyne's mind wRs the fact that the stones sent him were exceedingly minute none over the 12Sth of carat in weight, and therefore all but microscopioal. He could not see single entire crystal. All the fragments seemed as if they were broken bits of larger diamonds and one of the largest fragments more especially bore this character. The fact of their being broken Mr. Hannay attrib uted to the mechanical violence which they underwent on the heavy iron tubes in which they were crystallizsd being broken to get them out. Finally, Professor Maskslyne, though at present considering the discovery at best merely of scientific interest, was not altogether certain that now that the principle has been struck on larger stones might not eventually be produced. The stones sxhibi- ted filled glass tube not much bigger than quill and were so small that, as Professor Maskelyne remarked, it would take about thousand of them to make up the bulk of the smallest marketable diamond.