On Rain, Evaporation, &ec. 347 
i. Of the Quantity of Rain and Dew. 
2. Of the Quantity of Water that flows into the 
Sea. 
3. OF the Quantity of Water raised by Evapor- 
ation. 
4. Of the Origin of Springs. 
SECTION I. 
An Estimate of the Quantity of Rain and Dew that 
falls in England and Wales in a year. 
Rain-gages have been fixed of late years in 
almost every part of the kingdom ; by means of 
them we are enabled to determine, with con- 
siderable exactness, the depth of water that the 
rain yields in any given place. Inland counties 
have less rain than maritime ones, especially 
those which border on the western seas. But 
a still greater difference seems to take place be- 
tween a mountainous country anda champaigne, 
or flat country: In the former there often falls 
double or triple the quantity of rain in a year, 
that there does in the latter, and never less than 
an equal quantity. It may be observed, that 
several years account of the rain at any place 
is required before a medium yearly quantity can 
be obtained with sufficient accuracy. The fol- 
lowing is perhaps the largest collection of ac- 
counts of rain fallen in different places in Eng- 
