BODIES GENERALLY EXISTING AS GASES. I75 



this or the former fluids. On permitting the liquid in the tube to expand into gas, 

 and treating 1 00 parts of that gas with oil of turpentine, eighty-nine parts were dis- 

 solved, and eleven parts remained insoluble. There can be no doubt that the presence 

 of this latter substance, soluble as it is under pressure in the more condensable 

 portions, is the cause of the irregularity of the curve, and the too high pressure at 

 the lower temperatures. 



The ethereal solution of olefiant gas being mixed with eight or nine times its 

 volume of water, dissolved and gradually minute bubbles of gas appeared, the sepa- 

 ration of which was hastened by a little heat. In this way about half the gas dis- 

 solved was re-obtained, and burnt like very rich olefiant gas. One volume of the 

 alcoholic solution, with two volumes'of water, gave very little appearance of separating 

 gas. Even the application of heat did not at first cause the separation, but gradu- 

 ally about half the dissolved olefiant gas was liberated. 



The separation of the dissolved gas by water, heat, or change of pressure from its 

 solutions, will evidently supply means of procuring olefiant gas in a greater state of 

 purity than heretofore ; the power of forming these solutions will also very much 

 assist in the correct analysis of mixtures of hydrocarbons. I find that light car- 

 buretted hydrogen is hardly sensibly soluble in alcohol or ether, and in oil of turpen- 

 tine the proportion dissolved is not probably xsth the volume of the fluid employed ; 

 but the further development of these points I must leave for the present. 



Carbonic acid. — This liquid maybe retained in glass tubes furnished with cemented 

 caps, and closed by plugs or stop-cocks, as described, but it is important to re- 

 member the softening action on the cement which, being continued, at last reduces 

 its strength below the necessary point. A tube of this kind was arranged on the 10th 

 of January and left ; 'on the 15th of February it exploded, not by any fracture of the 

 tube, for that remained unbroken, but simply by throwing off* the cap through a 

 failure of the cement. Hence the cement joints should not be used for long expei-i- 

 ments, but only for those enduring for a few days. 



Oxygen. — Chlorate of potassa was melted and pulverized. Oxide of manganese was 

 pulverized, heated red-hot for half an hour, mixed whilst hot with the chlorate, and 

 the mixture put into a long strong glass generating tube with a cap cemented on, 

 and this tube then attached to another with a gauge for condensation. The heat of 

 a spirit lamp carefully applied produced the evolution of oxygen without any appear- 

 ance of water, and the tubes, both hot and cold, sustained the force generated. In 

 this manner the pressure of oxygen within the apparatus was raised as high as 58-5 

 atmospheres, whilst the temperature at the condensing place was reduced as low as 

 — 140° Fahr., but no condensation appeared. A little above this pressure the cement 

 of two of the caps began to leak, and I could carry the observation no further with 

 this apparatus. 



