18 Dr John Davy on the Production of Mist. 
recently erected—witness the Houses of Parliament—are not 
in progress of deterioration! Even within doors, unless due 
precautions be taken, articles of the greatest value, such as 
pictures and books, are liable to suffer from damp, especially 
the damp in question. I remember visiting an esteemed col- 
lection of pictures in the south of Devon, belonging to a noble- 
man not residing, and the rooms in which they were without 
fires, and being disappointed of an expected pleasure, owing to 
a precipitation of moisture on the paintings, almost completely 
obscuring them—the wind at the time blowing from the 
south, succeeding a continuance of cold weather with the wind 
from the opposite quarter. 
Nor is it undeserving of attention in relation to the appear- 
ances in nature and in connection with climate—and this irre- 
spective of the general consideration, that the aqueous por- 
tion of the atmosphere is the only one of its elements which is 
variable in a marked degree, and that were it not for this one, 
the aspects of the sky would be immutably the same. Not 
only are the low creeping mists of our valleys referrible to it, 
but also the clouds capping our mountains; indeed, the latter 
especially exemplify it :— 
« The south wind wraps the mountain top in mist.” 
So Homer sang as translated by Cowper. The same effect is 
witnessed at the present time in Greece ; as soon as the south- 
east—the moist warm sirocco—blows, all the mountain tops are 
hid, and more than that, a veil is, as it were, spread over the 
mountains themselves, either concealing them entirely, or 
allowing them to be seen dimly, like indistinct shadows through 
the vapoury air. The setting in of the same wind, often be- 
ginning very gently, is anticipated at Constantinople, by a 
dense fog appearing low over the surface of the Sea of Mar- 
mora, so low that whilst the hulls of ships becalmed in it are 
hid, their top-masts may be seen in the clear air above. 
To it, too, may be referred the large proportion of rain that 
falls in mountain districts, increasing in a certain ratio with 
the elevation of the mountains exposed to the impulse of warm 
or mild damp winds, of which we have so striking an instance 
in the Lake Districts of England ; where, in one spot, Scath- 
waite, in Borrowdale, in the midst of the higher ranges of hills, , 
the average fall of rain yearly is as much as 129-97 inches. 
