the Annual Evaporation at Liverpool, fee. 253 
be doubted, fays Dr. brownrigg in his very valuable 
work, The Art of making common Salt , but that double 
this quantity, or 60 inches, would have exhaled, had it 
been placed where the Sun and winds could have had 
their due effects fiJ . In another part of this publication, 
Dr. brownrigg fixes the evaporation of fome parts of 
England at 7 3.8 inches during the four fummer months, 
May, June, July, and Auguft; and the evaporation of the 
whole year at upwards of 140 inches/^. Thefe are cal- 
culations, however, which do not appear to correfpond 
with experience ; for the whole evaporation at Liverpool, 
inftead of 140 inches, was only 36.78 inches. The eva- 
poration likewife of the four fummer months, on a me- 
dium of four years, inftead of 7 3 inches, was only 18.88 
inches. 
3. Dr. hales calculates the greateft annual evapora- 
tion from the furface of the earth in England, even that 
from a furface of hop-ground, at 6.66 inches'^. If we 
compare this with the annual evaporation from a furface 
of water as determined by experiment, we find, that the 
latter exceeds the former about 30 inches; and that the 
annual evaporation from a furface of water, is to the an- 
nual evaporation from the furface of the earth in this 
part of England, nearly as 36 to 6, or as 6 to x. 
(b) Page 185. (c) P. 1S9. 
(d) Veg. Stat. vol. I. p. 55, 56, 
4. Oil 
