ture of April, as was asserted by Kirwan. The following result 

 has been here obtained. 



TABLE XXIV. 



48.35 

 49.84 

 48.98 

 48.09 

 49.18 

 47.31 

 47.88 

 50.46 

 50.51 

 48.13 

 51.06 

 48.12 



51.50 

 48.00 

 49.55 

 53.11 

 48.42 

 49.55 

 51.49 

 47.15 

 50.26 

 52.79 

 51.92 



52.39 

 52.61 

 50.71 



49.50 

 47.50 

 49.16 



44.40 

 50.74 

 44.94 



48.05 

 56.02 

 52.08 



Average, , 



49.04 



50.6 



I have naturally been anxious to ascertain how far the result of 

 these observations corresponds with the formula of Dr. Brewster, 

 and on this point have been favored with the following observations 

 by my colleague, Professor Ten Eyck. 



"Dr. Brewster's formula for finding the mean temperature of a 

 place is (mean temp. =86.3° Sin D-3*° ) or 86.3° multiplied by 

 the sme of the distance of the place from the nearest isothermal 

 pole,* and 3^° subtracted from the product. The result is the 

 mean temperature. The mean temperature at the equator in the 

 warmest meridian is 82.8°, and at the pole—SJo. 



The distance of Albany, Latitude 42° 38' 39" 

 Longitude 73 44 49, 

 trom the isothermal pole calculated by Dr. Brewster's formula is 

 380 34» 51?,^ an^j calculation i 

 50.3191°. 



