20 
Proceedings of the Iloyal Society 
2. On the Preparation of Adamantine Carbon or Diamond. 
By E. Sydney Mars den, D.Sc., F.K.S.E., F. Inst. Chem., &c. 
(Preliminary Notice.) 
The preparation of adamantine carbon or diamond has exercised 
the genius of philosophers from the very earliest times ; but it was 
not until the middle of the last century (1772) that Lavoisier 
established the diamond’s true nature — notwithstanding the sim- 
plicity of the experiments required to demonstrate the fact — and 
showed it to consist of pure carbon in a crystallised state. Since 
that time very many attempts have been made to prepare it arti- 
ficially, but until the recent and now famous experiments of Mr J. 
B. Hannay there has not been the slightest approach towards the 
solution of this problem. Great obstacles stood in the way of 
success, the chief being the complete insolubility of carbon in all 
known liquids, coupled with its non-volatility and infusibility ; 
while the subject was rendered even more difficult and obscure, by 
ignorance of the conditions under which the diamond is produced 
in nature, its peculiar crystalline form, together with extreme rarity, 
indicating a probable very slow formation, and rare natural existence 
of the conditions necessary for its formation. 
The process employed by me for the production of this substance 
is identical with the one for the preparation of pure adamantine 
boron which was worked out by Dr K. M. Morrison and myself, 
and communicated to this Society in a paper read June 17, 1878. 
It consists in dissolving the amorphous variety in fused silver or an 
alloy of platinum and silver, and allowing it to crystallize out again 
on cooling. This is effected in the following manner : — 
First of all we take a graphite crucible and line it inside with a 
layer of pure carbon half an inch in thickness — the carbon employed 
for this purpose is pure sugar charcoal mixed with a solution of gum 
into a firm paste and then tightly packed into the crucible, this is 
then very slowly dried and ultimately heated red-hot and allowed to 
cool again — the centre portion scooped out leaving the lining of 
half an inch thick, firm, solid, and compact, and without any cracks 
or holes ; to this special attention must be paid. 
The amorphous carbon (which is pure sugar charcoal prepared by 
