OBSERVATIONS ON THE FALL OF RAIN. 161 
power, for manufacturing or other purposes; in 
navigation or in draining ; in estimating its effects 
upon the country generally, or upon the course 
and mouths of rivers, and the maintenance of 
harbours, this knowledge is essential. 
It is a matter of surprise therefore, that so 
little has hitherto been done in the investigation 
of the subject. Dr. Dalton’s paper stands almost 
alone, and, until recently, no actual observations 
upon a large scale, appear ever to have been 
made. 
Valuable, however, as the Doctor’s reasoning 
and calculations undoubtedly are, they can only 
be regarded as mere approximate estimates ;_ but 
they are grounded upon the proper data, the best 
he could at that time command, and are well cal- 
culated to account in all respects most rationally, 
for the manner in which the water of rain is 
disposed of. 
To arrive at accurate conclusions, such as may 
be depended upon with confidence, in applying 
the results to the purposes of life, extensive ob- 
servations upon a large scale, for a long series of 
