Mr Graham on the absorption of Vapours by Liquids. 331 



which each liquid acquired during that period. These liquids 

 were afterwards withdrawn from the tin-vessel and freely ex- 

 posed to the air, that they might evaporate, in order that the 

 connection between their evaporating and invaporating power 

 might be observed. The loss of each liquid by evaporation 

 during twenty-four hours is placed against it in a third co- 

 lumn. 



A capsule of pure water was allowed to evaporate spontane- 

 ously for the same time as the cases in the table. It lost 13.9 

 grains. The temperature of the air did not exceed 45°. The 

 similarity of the point of ebullition seems to be attended with 

 an analogous increase from invaporation and loss by evapora- 

 tion in the saline solutions and in tartaric and sulphuric acids. 

 The difference of the results in these cases is so small that it 

 might depend on slight variations of the form of the capsules, 

 or other accidental circumstances. But the absorbing power 

 of the two cases of muriatic acid and of nitric acid, which boil at 

 the same temperature, are exceedingly different. The stronger 

 muriatic acid also actually gained weight when exposed to the 

 air, instead of sustaining loss by evaporation, like the other 

 cases. The weaker muriatic acid and the nitric acid likewise 

 lost less by evaporation, as they gained more by invaporation 

 than the saline solutions. The invaporating powers of liquids 

 appear to be reciprocally proportional to their evaporating 

 powers, as might be expected. This was observed very dis- 

 tinctly on exposing to the air various saline solutions of dis- 

 similar absorbing power, when those which invaporated in the 

 least degree evaporated most rapidly, and vice versa. 



It has not, I believe, hitherto been noticed, that muriatic 



