DISTRICT OF CUMBERLAND AND WESTMORELAND. 
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country, and with little diminution of its weight or volume ; but on reaching the 
mountains, it meets with a temperature many degrees lower than the point at which 
it can continue in a state of vapour ; sudden condensation consequently ensues in 
the form of vast torrents of rain, which in some instances must descend almost in 
a continuous sheet, as when 9 or 10 inches are precipitated in forty-eight hours. 
When we reflect that a warm moist current, perhaps only 3° or 4° above the point 
of saturation, in coming in contact with the mountain ridge, probably meets with a 
stratum of air 10° or 15° lower than its own inherent temperature, we shall cease to 
marvel that such quantities as four or five, or even six perpendicular inches of water 
should be deposited in these localities in the course of a few hours. The mountains 
are, in fact, huge natural condensers, destined to force from the atmosphere the 
mighty volumes of water requisite for the supply of our lakes and rivers. 
I have before stated that I am unable to offer any satisfactory reason for the great 
excess of rain at Seathwaite over all the other valleys ; judging from its situation, I 
should, a 'priori, have looked for the greatest fall at Wastdale Head, as it is sur- 
rounded by the highest mountains, and the valley opens out fairly to the south-west. 
But the maximum quantity is found to obtain, not where theory would indicate, but 
in the very identical spot where it is most required, — in the vale of Borrowdale, which 
affords the principal supply of water to the extensive and picturesque lakes of Der- 
went and Bassenthwaite ; thus adding one more to the multitudinous instances which 
surround us, of the wonderful adaptation of external nature to the physical wants 
and requirements of man. 
Whitehaven, March 15, 1848. 
MDCCCXLIX. 
N 
