h}i IVafrr aiul olhi'v Liquids, 275 



9. Most liquids irci: iiuiu viscidity, such as 

 acids, alcohol, liquid sulphurets, and saline 

 solutions in water, absorb the same quantity of 

 gase^ as pure water; except they .have a a 

 affinity for the gas, such as the sulphurets for 

 oxygen, &c. 



The preceding articles contain the prin- 

 cipal facts necessary to establish the theory of 

 absorption : Tliose that follow are of a subor- 

 dinate nature, and partly dcducible as corrol- 

 laries to them. 



10. Pure distilled water, rain and spring 

 water usually contain nearly their due share of 

 atmospheric air : if not, they quickly acquire 

 that share by agitation in it, and lose any other 

 gas they may be impregnated wnth. It is re*- 

 markable however that water by stagnation, 

 in certain circumstances, loses part or all of its 

 oxygen, notwithstanding its constant expo- 

 sition to the atmosphere. This 1 have uni- 

 formly found to be the case in my large w^ooden 

 pneumatic trough, containing about 8 gallons, 

 or 14" cubic foot of w^ater. Whenever this is 

 replenished with tolerably pure rain water, it 

 contains its share of atmospheric air ; but in 

 process of time it becomes deficient of oxygen; 



^v,... / ., ,,.ji present li.. /.<./.^ ..^vv. i$ formei which require^ 

 just half the quantity of jxitroiv? gas, as I have ktely ascer- 



M m 2 



