1856.] 



Report on tlie Magnetic Survey, 



565 



heated air, corresponding with the temperature of the mercury, 

 which, during the periods of stronger wind, was removed, and re- 

 placed by one less hot. 



The readings were 



At 1-42 p. M 82.60 Centigrade. 



(Wind increasing very much at 1.44 p. m.) 



Thermometer at 1.46 p. M 78.74 „ 



It rose again, in a slight lull, from 1.53 to 2.10 p. M. 



It stood at 2.10 p. M 80.45; 



then the wind setting in again, it gradually sank, and soon (2.35 

 p. m.) disappeared below the divided scale. 



At Allyghur, April 17th, the day was particularly clear ; the 

 "West wind hot, but not very strong. Here I found the highest 

 temperature I had yet observed, viz. 90° 30 C. or 194 54 E, # the 

 time of this maximum, 1.20 p. M., coinciding very nearly with that 

 observed at Benares. 



I was enabled to compare my instrument with one used by Mr. 

 Gubbins,t the bulb of which was protected against lateral radiation, 

 by being enclosed in a double cylinder of glass. The two instru- 

 ments agreed, at least for the maximum, better than might have 

 been expected. The time of the maximum was naturally, not so 

 well denned in the one enclosed in the glass tube, as in the other 

 lying on wool : the former was too cold before the period of its 

 maximum, too warm afterwards. The readings were on April 3rd — 





Schlagiwtweit. 



Hypsometer 

 No. 5. 



Gtibbins. 

 In glass cylinders. 



Black bulb 

 exposed free. 



12-0 . . . A 

 1-15 . . . .[ 

 1-20 . . . . [ 

 1-45 . . . . f 

 2-35 . . . A 



88.58 C. 

 191.44 F. 



90.13 C. 

 194.23 F. 



90.30 C. 

 194.54 F. 



86.10 C. 

 186.98 F. 



80.60 C. 

 177.08 F. 



] 190.5 



~) Disturbed by ap- 

 ) proaching too near. 



] 189.5 

 ] 188.0 

 ] 185.0 



126.0 

 ] 127.1 

 128.5 

 119.0 

 122.0 



* Corrected as the following for index error. 



t We are deeply indebted to Mr. and Mrs. Gubbins for the communication of 



