Transactions. 



249 



separately, along with the state of the river or the mean dejitli as 

 registered at the gauge (which was erected in July), viz. : — 



Means for whole year 52-8° 



48-5° 



48-5° 



Mean diU'eience between air 



and water for year 4 '3° 



From this table it will be seen that the highest monthly mean 

 temperature of the air for the year was in June, when it was 65 "8°, 

 the mean temperature of the water for the same month being G3°, 

 also the highest mean for the year. The lowest was in December, 

 when that of the air was 40-2* — water, 38-2° ; but the mean tem- 

 perature of February for the water was a fraction lower than this, 

 viz., 38 r, while that of the air was 42-8°. Range for monthly 

 means — air, 65'8° ; water, 38"1° — 27*7°. 



The highest single reading for the air was on 31st July ... 76° 



The lowest single reading for the air was December ... .. 31° 



Extreme range for air ... ... ... 45° 



Highest .single reading for water was on 4th July ... ... 66 '6° 



Lowest single reading for water was on 13th February ... 32° 



E,\;treme range for water .. . ... ... ... 34 "6° 



The months in which the mean monthly temperature of the air 

 and water most nearly approximated were : December, when the 

 difference was only 2° (i.e., of air above water) ; November, 2-.5° ; 

 June, 2 '8° ; and July, 3°. Those in which the temperature varied 



