1880.] On the Artificial Formation of the Diamond. 457 



explosion, induces a nervous state which is extremely weakening, and 

 when the explosion occurs it sometimes shakes one so severely that 

 sickness supervenes. 



It appeared that as the bone oil had so hardened the carbon, if it 

 acted upon nascent carbon it might harden it so much as to produce 

 diamond. An experiment was accordingly tried in which bone oil 

 distillate and paraffin spirit were mixed, so that when an alkali metal 

 was made to act upon it the decomposition of the hydrocarbon might 

 yield carbon which would be crystallized by the action of the nitro- 

 genous liquid. The proportions used were 90 per cent, bone oil, and 

 10 per cent, paraffin spirit, with lithium as the metal. The tube used 

 was a coil-tube of Lowmoor iron, 4 inches in external, f-inch internal 

 diameter, and 24 inches long. Three grms. of lithium was employed, 

 and the tube filled three parts of its length with the mixed liquids, 

 a little lamp-black added, and welded up. It was heated 14 hours 

 to a dull red-heat, and then bored open. A very high pressure was 

 found to exist inside the tube, and as the material was at the other end 

 •of the tube it was removed by a long punch. It was found to be a 

 mixture of carbon and lithium compounds, with some cyanides. Some 

 -of the carbon was very hard, but could be crushed by agate, and would 

 not scratch it ; but there was mixed with it (as with many of the other 

 experiments) a few grains of silica. This was, perhaps, introduced in 

 the welding, as a little silica had to be employed here, and a little may 

 have been added with the lamp-black, which was never quite free from 

 sand or other accidental impurity. The silica particles were easily re- 

 moved by placing the substance on the stage of the microscope, and 

 examining by polarized light, when all the particles which showed 

 rotary power were removed. 



The results obtained by the use of the two liquids being so much 

 more satisfactory, further experiments were undertaken in this direc- 

 tion, and a series of four tubes filled with varying proportions. The 

 tubes had the dimensions 20" X 3f" X \" bore, and had 3 grms. of 

 lithium introduced into each and then filled as follows : — 



No. I. 80 per cent, bone oil, 20 per cent, paraffin spirit^ 5 grms. of 

 „ II. 40 ,, „ 60 ,, „ I lamp-black 



„ HI. 20 „ ., 80 „ „ r added to 



„ IV. 10 „ „ 90 „ „ J each. 



These were heated separately in the furnace, with the result that 

 Nos. I and III burst, and Nos. II and IV withstood the pressure. 

 No. II on being bored open gave off a great volume of gas, but on 

 removing the contents nothing but lithium compounds and soft carbon 

 was obtained. No. IV also evolved much gas, but the solid matter 

 was very hard and contained some hard particles of carbon, but no 

 diamond. It seemed therefore probable that some such proportion of 



