232 ° Caleb Atwater on the Winds of the West. 
From several gentlemen, residents for several years in lilinois 
and Missouri Territories, 1 have been informed, that changes 
of weather in that region of country are, especially in winter, 
very frequent and great; that one day the moist south wind from 
the Mexican gulf will prevail, and produce quite warm and mild 
weather for the season; on the very next, or frequently the latter 
part of the same, the current of air from the sources of the Mis- 
souri will prevail, and block up the streams with ice. 
There isa third current of air which prevails during our 
winter months, more and more, annually, as the country becomes 
cleared of its forests in the direction alluded to; it proceeds from 
the great lakes to the northwest of us, and even beyond them. 
Proceeding as it does from the north and northwest of lake Su- 
perior, and crossing the great expanse of water in this direction, 
it rushes down these great lakes to the south end of lake Michi- 
gan in latitude about 41° north, diverges from that point, and 
spreads over the immense regions lying to the south, where. the 
air is more rarefied by reason of its warmer climate. This cut- 
rent of air brings along with it intense cold, and extended last 
winter even to New-Orleans, where the snow fell to sucha depth, 
that sleighs were seen passing in every part of the city. The 
more the forests are cleared away between any place in this coun- 
try and the northern lakes, the more this cold current of ait will 
prevail. ‘This current also diverges from the southern shore of 
Lake Erie, but is not so strong as that part of it which diverges from 
the south end of Michigan, and of course does not extend a8 far 
to the south. When this part of this state was first settled, this 
current of air was hardly felt at this place, and then only for a 
short time in the winter months, and hardly ever reached the Obio 
river > but last winter it continued three weeks at one time, and 
produced good sleighing; and also 1 rk tisms, pleurisies, 
peripneumonies, &c. which proved mortal to some. In this place, 
which is in latitude about 39° 20’ north, the thermometer of 
Fahrenheit, hanging in an entry of a dwelling-house with closed 
doors, sunk to 24 degrees below zero. This extreme cold may 
