280 
POPULAR SCIENCE REVIEW. 
A careful examination for felspar and schreibersite was made, but 
with a negative result. ( American Journal of Science , June, 1880. [3] XIX. 
459.) 
On the Artificial Formation of the Diamond . — The second paper giving in 
detail the method employed with success by Mr. J. B. Hannay in forming 
diamonds artificially, has recently been communicated to the Royal Society, 
and is deserving of a short notice. The amount of hydrogen taken up by 
sodium was determined, and it was found that as much as thirty-two times 
its volume could be removed from it after it had been allowed to act on 
paraffin spirit. The sodium was often found to contain carbon of a hard, 
scaly nature, and ‘this was the reaction on which my work was built.’ 
Potassium yielded less satisfactory results ; lithium acted better, the carbon 
which it liberates by the action of paraffin spirit will often scratch glass 
easily. For the diamond experiments the material was heated in iron tubes, 
and tube after tube exploded and all was lost. It was often found on boring 
open a tube that the interior was harder than the exterior and converted 
into steel. To meet this loss of carbon some lampblack was added to the 
contents of the tube. Iron tubes 20" x 2" x |" bore were used, and 
three grammes of sodium were employed, the tubes being filled from f to f 
full of paraffin spirit and then welded together. The tubes exploded during 
the heating, and recourse was had to tubes on the coil principle, and two 
were constructed of the toughest bar iron, made solid, and bored out after- 
wards. The dimensions were 20" x 2|" x | bore ; the tubes contained three 
grammes of sodium, \ gramme of lampblack, and were filled two-thirds full 
of paraffin spirit. The heat was kept up for eight hours ; both kept tight, 
and furnished a little scaly carbon ; other tubes containing lithium burst, 
and it became evident that still stronger tubes would have to be used. A 
tube measuring 2|" x 20" x bore was employed, and in it was placed some 
‘ bone oil ’ (the nitrogenous distillate obtained in the manufacture of bone 
char), and charcoal powder, and the tube welded up solid. It was heated to a 
dull red-heat for fourteen hours and allowed to cool. On opening the tube 
there was a great out-rush of gas, and the carbon was to a certain extent 
dissolved and some minute portions of it were very hard. It appeared that 
bone oil had the power of hardening the carbon, and if it acted upon nascent 
carbon it might harden it so much as to produce diamond. An experiment 
was made in which bone oil and paraffin were mixed, so that when an 
alkaline metal was made to act upon it the decomposition of the hydro- 
carbon might yield carbon which could be crystallized by the action of the 
nitrogenous liquid. The proportions taken were 90 per cent of bone oil and 
10 per cent of paraffin, with lithium as the metal. A very strong tube was 
filled and welded together and heated to a dull red heat for fourteen hours. 
When bored open a very high pressure was found inside the tube ; the 
carbon was very hard but could be crushed by agate and would not scratch 
it. The results, however, when two liquids were used, were so much more 
satisfactory, that further tubes were filled, welded and heated. A tube 
measuring 20" x 4" x bore was filled with four grammes of lithium, bone 
011 90 per cent and paraffin 10 per cent, and heated for fourteen hours. 
When opened, a large amount of gas was given off. In the end of the tube 
which had been in the upper part of the furnace there was a hard, smooth 
