THE WEATHER FOR NOVEMBER. 
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valley of the Forth and Clyde canal; and to all the remainder the mountains 
of the south of Scotland, of England, and of Wales, present a barrier generally 
insuperable to the east winds from the continent. 
The west wind, or wind at south-west, is the natural direction of the atmo¬ 
spheric current in Britain, where that current is the return occasioned by the 
trade winds further to the south. As such, it is generally loaded with mois¬ 
ture up to the point of saturation, or nearly so ; and the result is a greater 
humidity of the Irish climate than of the English, and a more rainy atmo¬ 
sphere all along the western side of Britain than along the eastern. 
When the surfaces of the north and north-eastern regions of Europe are 
heated by the drought, which is, generally speaking, longer and more pro¬ 
tracted than in Britain, there is an acceleration given to the eastern atmo¬ 
sphere which extends over Britain and the intervening sea to the continent; 
and in this state of things, the atmosphere, except where affected by local 
causes, such as downs and plains, mountains and valleys, is comparatively 
tranquil ; and, to what distance soever it may extend, this south-westerly wind 
is always favourable to wholesome vegetation. Upon the low and heated 
shores of the west the quantity of rain is not so great as it is inland towards 
the heights, because the cold air which the current has to encounter on these 
heights reduces the temperature of the whole, and consequently its capacity 
for moisture ; and, independently of all local causes, there may be rain on the 
central, or spinal, mountains and hills, when there is dry weather both to the 
eastward and to the westward of them. But it is the upland slopes, toward 
the west, upon which rain falls the most abundantly; and it diminishes the 
temperature, and produces showery weather, which, though admirably adapted 
to the growth of potatoes and fruits, does not answer so well for wheat as 
climates which are less showery. 
When the current of the atmosphere is from any point between the north 
and east, the state of things is reversed and unnatural. Where this is the case, 
the cold winds from the continent may counteract the natural current from the 
south-west as far as the western shores of Britain. These east winds, when 
they quit our eastern shores, are not saturated with humidity; and therefore 
they produce blighting winds in the spring, and deluges of autumnal rain on 
some parts of the country, although the west wind, which still continues at a 
certain height above the sea, is the source out of which the deluges of rain, 
with an easterly wind on the surface, are produced. 
There are two principal seasons of those effects of east wind,—the blighting 
winds of spring, and blighting winds again during the autumn, the latter being 
those which are accompanied by the most heavy deluges and floods. The 
spring blights are occasioned by a premature heating of the surface of the 
country; and they continue drying winds until the central heights are arrived 
at. The severe wind of autumn is produced by an unduly protracted 
autumn, which blows across the country, and mingles with, and overcomes, the 
west wind, which is opposed to it; and the quantity of moisture above what 
serves to saturate the compound is, as in all similar cases, deposited on the 
earth in water or in snow, according to the locality. If the character of the soil 
be such as to render it easily cooled by evaporation, this produces the same 
effect as is produced in other places by greater altitude ; and hence there is 
