i86 



Table IW. 

 PRESSURE OF AQUEOUS VAPOR IN THE ATMOSPHERE- 



This table gives the vapor pressure corresponding to various values of the difference I — li between the readings of 

 dry and wet bulb thermometers and the temperature h of the wet bulb thermometer. The difference I — h is given 

 by two-degree steps in the top line, and t\ by degrees in the first column. Temperatures in Centigrade degrees, vapor 

 pressures in millimeters of mercury are used throughout the table. The table was calculated for barometric pressure 

 B equal to 76 centimeters. A correction is given for each centimeter at the top of the columns. Ventilating velocity 

 of wet thermometer about 3 meters per second. 



Smithsonian Tabues. 



