EVAPORATION AT PALERMO. 



46i 



Months. 



Jamiary . . 

 JFebruary . 



Marcli 



April 



May 



Juue 



July 



August ... 

 September 

 October . . 

 November 

 December 



S ® 



+10. 98 

 11.15 

 12. 42 

 14.86 

 18.59 

 22.34 

 25. 04 

 25.22 

 22. 98 

 19.68 

 15.57 

 12.30 



.5 >:> 



78.7 

 77.7 

 77.2 

 76.1 

 73.5 

 72.0 

 70.1 

 69.3 

 73.5 

 75.7 

 75.9 

 80.7 



Sin h. 



0.515 

 0. 630 

 0.768 

 0.882 

 0.945 

 0. 967 

 0.958 

 0.911 

 0.816 

 0. 682 

 0.548 

 0.478 



2.595 



2.982 

 3.654 

 4.508 

 5.502 

 6. 366 

 6.925 

 6. 838 

 6. 034 

 4. 926 

 3.682 

 2.730 



5"^ 



80. 



84. 

 113. 

 135. 

 170. 

 190. 

 114. 

 211. 

 181. 

 152. 

 110. 



84. 



By seasons. 



Winter 249.32 



Spring 419.07 



Summer 617.64 



Autumn 444. 19 



Annual mean . 1, 730. 22 



In relation to rain, by comparing the total monthly evaporations with 

 the mean quantity of water which falls in each month, and which will 

 be found recorded in one of the preceding tables, it will be seen that 

 the evaporation according to the Gasparin apparatus is about equal to 

 the rain only in the months of January and December, being alicays 

 greater in the other months ; the annual evaporation is very nearly 

 thrice the height of the water ichich falls, and equal to once and a third 

 of that in the shade, or as denoted by the atmometer of Vivenot. From 

 the quantities of the monthly evaporation calculated after both instru- 

 ments let us take the differences referable to the different positions of 

 the atmometers, and transcribe them in connection with those actually 

 verified in 18G6. G — Y indicates the Gasparin evaporation less that of 

 the Vivenot atmometer. 



Differetices. 



G — V from calculation. G — V observed in 1866. 

 Millimeters. Millimeters. 



January +10. 08 — 8. 78 



February. +10. 12 + 3. 74 



March +33. 69 +33. 11 



April +43. 08 +59. 59 



May +51.43 +41.20 



June +52. 41 +53. 99 



July +54. 22 +62. 19 



August +50. 34 +50. 51 



September ... +38. 49 +27. 30 



October +26. 60 — 7. 97 



November +13. 92 —10. 43 



December + 5. 77 + 5. 61 



The above differences, if we consider the disturbances to which the 

 Gaspariu atmometer is exposed from raiu and clouds, discover a suffi- 

 30 s 



