232 THE CHEMISTRY OF CREATION. 



our senses fails to render us any account of the 

 ingredients forming the atmosphere, mingled 

 together in the proportions in which we find 

 them. Pure air is without odour or taste, and is 

 so transparent that the exhausted receiver of an 

 air-pump presents the same appearance to the 

 eye as it did when full of air. 



While, then, we remain in this pleasant 

 country spot, far from the busy hum of men, and 

 listen to the important facts detailed upon the 

 chemical history of the gentle breeze, let us not 

 forget that we owe all that we know on this sub- 

 ject to the long-continued and persevering labours 

 of the experimental chemist in his often dark and 

 smoke-filled laboratory. 



