Bcsults of Some Experiments npon the Bate of Evaporation. 49 



January . . 

 February 

 March . . 

 April .... 



May 



June .... 

 July .... 

 August . . 

 September 

 October . . 

 November 

 December 



8-incli 

 Copper Pan. 



Inches. 

 •52 

 •60 

 •35 

 •25 

 •17 

 •18 

 •17 

 •27 

 •45 

 •55 

 •58 

 •52 



Screened 

 Tub. 



Inches. 

 •35 

 38 

 24 

 16 

 15 

 11 

 12 

 24 

 37 

 41 

 46 

 42 



Tank. 



Inches. 

 •37 

 •38 

 •22 

 •16 

 •09 

 •08 

 •08 

 •16 

 •26 

 •31 

 •36 

 •35 



Piche 

 Tube. 



Inches. 

 •43 

 •46 

 •29 

 •20 

 •21 

 •22 

 •22 

 •31 

 •49 

 •51 

 •51 

 •38 



For the purpose of showing how these different values have beert 

 influenced by the elements of climate, we give below in six columns 

 (1) the mean temperature, humidity, and wind movement, of the 

 successive months, derived from hourly observations, and (2) the 

 mean temperature, humidity, and wind movement of the day, upon 

 those days which saw the maximum amount of evaporation from the 

 tank in each month : — 





Mean Valxtes. 



Extreme Values. 





Air 



Temp. 



Humidity. 



Wind. 



Miles 



per day. 



Air 



Temp. 



Humidity. 



Wind. 



Miles 



per day. 



1900 



January 



February 



March 



April 



May 



June 



July 



August 



September .... 



October 



November .... 

 December .... 







75 

 77 

 71 

 65 

 58 

 51 

 50 

 53 

 65 

 67 

 72 

 72 



% 

 50 

 46 

 64 

 69 

 56 

 62 

 68 

 53 

 39 

 41 

 39 

 56 



134 

 146 

 123 

 86 

 78 

 118 

 116 

 128 

 138 

 168 

 175 

 159 







74 

 80 

 74 

 66 

 63 

 56 

 53 

 56 

 73 

 77 

 78 

 71 



/o 



45 

 38 

 47 

 62 

 55 

 55 

 58 

 36 

 28 

 28 

 32 

 46 



161 

 18 

 136 

 135 

 38 

 142 

 152 

 163 

 283 

 130 

 176 

 196 



We notice that the air is much dryer than the mean in each 

 instance of maximum evaporation, and the wind a good deal stronger 

 in nearly every instance. But, singularly, the air, which under 

 assigned conditions as to the total quantity of contained moisture, 



4 



