332 



APPENDIX 



COMPARISON OF CENTIGRADE SCALE WITH FAHRENHEIT: t C.= - 1 + 32 FJ 



SOME CONSTANTS CONCERNING AIR. 



Weight of one liter of air at the barometric pressure of 760 

 mm. and the temperature of o C., 1.293 grams. Per cent., by 

 weight, of oxygen in pure air under above conditions, 23.18^0. 

 Per cent., by weight, of nitrogen (including argon) in pure air 

 under above conditions, 76.82/0. Per cent, of CO 2 varying 

 quantity usually taken at 0.03-0.04^ HNO 3 and NH 3 present as 

 traces under some conditions. 



Amount of water vapor contained in saturated air at the pres- 

 sure of 760 mm. and at various temperatures. 



oC. 4.835 20C. 17.118 



5 6.761 25 22.796 



10 9.330 30 30-039 



15 12.712 35 39.187 



1 Smithsonian Tables, 1897. 



