1825.] obtained by the Decomposition of Oil. 159 



like water and some saline solutions, be cooled much below 

 that point before any part becomes solid. It contracts very 

 much on congealing, 9 parts in bulk becoming 8 very nearly ; 

 hence its specific gravity in that state is about 0*956. At 

 it appears as a white or transparent substance, brittle, pulveru- 

 lent, and of the hardness nearly of loaf-sugar. 



It evaporates entirely when exposed to the air. Its boiling- 

 point in contact with glass is 186. The specific gravity of 

 its vapour, corrected to a temperature of 60, is nearly 40, 

 hydrogen being 1 ; for 2'3 grains became 3*52 cubic inches of 

 vapour at 212. Barometer 29*98. Other experiments gave 

 a mean approaching very closely to this result. 



It does not conduct electricity. 



This substance is very slightly soluble in water ; very soluble 

 in fixed and volatile oils, in ether, alcohol, &c. ; the alcoholic 

 solution being precipitated by water. It burns with a bright 

 flame and much smoke. When admitted to oxygen gas, so 

 much vapour rises as to make a powerful detonating mixture. 

 When passed through a red-hot tube, it gradually deposits 

 carbon, yielding carburetted hydrogen gas. 



Chlorine introduced to the substance in a retort exerted but 

 little action until placed in sunlight, when dense fumes were 

 formed, without the evolution of much heat; and ultimately 

 much muriatic acid was produced, and two other substances, 

 one a solid crystalline body, the other a dense thick fluid. It 

 was found by further examination, that neither of these were 

 soluble in water ; that both were soluble in alcohol the liquid 

 readily, the solid with more difficulty. Both of them appeared 

 to be triple compounds of chlorine, carbon, and hydrogen ; 

 but I reserve the consideration of these, and of other similar 

 compounds, to another opportunity. 



Iodine appears to exert no action upon the substance in 

 several days in sunlight; it dissolves in the liquid in small 

 quantity, forming a crimson solution. 



Potassium heated in the liquid did not lose its brilliancy, or 

 exert any action upon it, at a temperature of 186. 



Solution of alkalies, or their carbonates, had no action 

 upon it. 



Nitric acid acted slowly upon the substance and became 

 red, the fluid remaining colourless. When cooled to 3% 9 the 



