20 



RATIO OF SPECIFIC HEATS. 



Several series of experiments which after a long iuterval of inactivity were 

 obtained with a new sulphuric-acid manometer and a more accurate cathetometer 

 are now to be given. The first series of exj)erimeDts was conducted on March 13, 

 1894:, under conditions of low barometric height, 74.42 cm., and for a relatively low 

 temperature, 11.91° C, of the water bath. At this temperature the balancing resist- 

 ance in the Wheatstoue bridge at Z was 



rr, = 70 + 10 + 2 + I + 2* + .2, 

 of which 2* -|- -2 ohms were inserted before opening the charged receiver, Mai'ch 

 13, 1894. 



The pressure value corresponding to the divi.sion 14.21 on the acid manometer 

 was therefore considered correct. Its value was found from the following pressure 

 comparison made when the temperature of the mercury was 20° C. 



