Chemical Science. 157 



on it some time before it became all vapour. As the tube cooled 

 the green colour diminished by degrees, and the fluids took their 

 first state except that the water was of a yellowish tinge, which, 

 however, was much diminished by agitation. 



The tube was again heared, with the intention of converting all 

 the water into vapour, but soon aftnr the deep green colour appeared, 

 the tube broke. 



Another tube, besides the same liquids, contained also a little 

 chlorate of potash. The first effect of the heat was to dissolve the 

 salt ; on leaving it to cool, the water became milky, and the sulphuret 

 of carbon, which previously floated, fell to the bottom with the 

 crystallizing salt. Exposed to a higher heat, the liquor became of a 

 sudden of a fine lemon yellow colour, accompanied with efferves- 

 cence, and the formation of an oily looking globule which, when 

 all was cold, remained liquid at the bottom of the tube, but no 

 crystals were now deposited. 



The tube being heated still more highly, the yellow liquid dis- 

 appeared and was replaced by a small globule of liquid sulphur ; 

 this at a higher heat took on the colour and transparency of the 

 ruby, but, when all was cold, had the ordinary appearance of sul- 

 phur. No trace of sulphuret of carbon appeared in the tube, except 

 that when heated to a certain degree, the water became of a bluish 

 colour. When cold the water was colourless and transparent. This 

 coloration did not take place in another tube into which a larger 

 proportion of chlorate of potash was put. 



Sometimes small acicular crystals formed in these tubes, grouped 

 five or six about a central point ; sometimes nearly the whole mass 

 was crystallized, this effect was only once obtained. On breaking 

 the tube a very strong explosion took place, and the fluid was ex- 

 pelled from the tube; the water was strongly acid. It is remarkable 

 that in these experiments the water did not at all effect the transpa- 

 rency of the glass, though, when alone, it produces that effect very 

 rapidly. — Ann. de Clrim. xxiii. 267. 



2. Fusion of Charcoal, Plumbago, Anthracite, and Diamond ; pro- 

 bable productions of Diamonds, by Professor Silliinan. — Professor 

 Silliman has lately been very active in ascertaining the effect of in- 

 tense heat on charcoal, plumbago, and anthracite. The instruments 

 he t used were Dr. Hare's galvanic deflagrator and his compound oxy- 

 hydrogen blow-pipe. Fusion was generally produced, and, in some 

 cases, results which apparently approximate so nearly to diamond as to 

 give great interest to the experiments. The following passages are 

 partly extracted, partly condensed from some of his papers on the 

 phenomena. The papers at length may be referred to in Silliman's 

 Journal, vol. vi. 



With regard to the fusion of plumbago, the best results were obtained 

 when the plumbago was connected with the copper pole, and prepared 



