OBSERVATIONS. 67 



The observations were made once a week, and 

 the general annual mean found from them is 

 48*^.8, bemg .4 of a degree higher than that 

 determined by means of Rutherford's thermo- 

 meters, for the same period. The surface of the 

 water in the well, below that of the ground, 

 varies from about 3 to 6 feet. 



I2 



