RADIATION 63 



a current of dry air into the tube already employed for 

 gases and vapors: 



Name of perfume Absorption 



Patchouli 30 



Sandal wood 32 



Geranium ......... 33 



Oil of cloves 34 



Otto of roses ........ 37 



Bergamot 44 



Neroli 47 



Lavender . 60 

 Lemon .....65 



Portugal ......... 67 



Thyme 68 



Rosemary , . . T4 



Oil of laurel 80 



Camomile flowers ....... 87 



Cassia 109 



Spikenard 355 



Aniseed 372 



Thus the absorption by a tube lull of dry air being 1, 

 that of the odor of patchouli diffused in it is 80, that of 

 lavender 60, that of rosemary 74, while that of aniseed 

 amounts to 372. It would be idle to speculate on the 

 quantities of matter concerned in these actions. 



12. Aqueous Vapor in relation to the Terrestrial 

 Temperatures 



We are now fully prepared for a result which, without 

 such preparation, might appear incredible. Water is, to 

 some extent, a volatile body, and our atmosphere, resting 

 as it does upon the surface of the ocean, receives from it 

 a continual supply of aqueous vapor. It would be an 

 error to confound clouds or fog, or any visible mist, with 

 the vapor of water, which is a perfectly impalpable gas, 



