The Anderson intelligencer. [volume] (Anderson Court House, S.C.) 1860-1914, 1888-05-17
inward and rises high in the air to pass

upward and rises high in the air to pass
over. In SO doing it becomes cooled,
giving up its moisture, and passes over to
the other side a dry wind. tits for this
reason that some islands like the Hawai-.
ian Islands in the Pacific Ocean, where
the winds blow almost always from the
same direction, are subject to almost
continuous rain on one side, while on the
other rain is exceedingly rare. This
also shows why California, West of the
Sierra Nevada Mountains, receives sufti.
cient rain to make the soil ht for cultiva.
tion, while Nevada, on the East, is nearly
rainless and barren. The moisture com.
ing from the South and East is all
condensed by the Allegheny, the Rocky
and the Wahsatch ranges, while that
from the West is cut off by the sierras.
Hence the great extent of country known
to geologists as the Great Basin-which
reaches from Oregon on the North to
Mexico on the South, and from Colorado
on the East to the Sierras on the West,
comprising an area of not less than 200,-
600 square miles, which is nearly equal
to the whole of Frsnce-receives over q
great part of its surface an annual rain;
fall of not over four inches, and is there.
fore a desert.
There are many other interesting facts
about this vapor. Let US consider 8
few.
After the sun goes down at night,
the earth cooling rapidly soon cools the
air near it, which consequently gives up
q part of it's moisture. This moisture
forms in drops on the grass and leaves,
just as it does on the cold pitcher in the
warm room, and we call this "dew." If
it becomes cold enough the dew freezes,
and we then have "frost." On cloudy
nights frost is very rare, simply because
the clouds act as tent or blanket, and
prevent the earth from becoming cooled
so rapidly. Professor Tyndall has calcu-
lated that of all the heat daily received
by the earth from the sun and given off
again into space, one.tenth is intercepted
and absorbed by the vapor of water
within ten feet of the earth's surface.
Hence, the vapor forming the clouds
above, and extending in its invisible
form down to the earth, absorbs the heat
given of, and, like the glass screen in
hot house, prevents the earth becoming
80 cool as to freeze the dew. This fact
will enable US to understand, in part, why
it is that deserts and all dry regions are
subject to such sudden extremes of tenn.
perature, being very hot when the sun is
shining, but becoming chilly as soon as
the sun goes down.
Moreover, water, and consequently
anything wet with water, takes up and
parts with heat much more slowly than
dry land and water and other liquids,
when evaporating, take away a great
amount of heat with the yapor. The
more rapid the evaporation, the greater
the amount of heat taken up in given
time. This is the reason drop of ether
feels cold when placed on tho hand. It
evaporates so rapidly as to take away the
heat from the skin quicker than it is
restored, and produces the same feeling
as would q piece of ice.
Now we are ready to understand why
it is that hot day in dry climates is
much less oppressive than in moist eli.
mates. People who live in the East and
South, where the air is full of moisture,
read that the temperature on hot day
in the West rises as high as 100 or ITO
degrees, and they think the West must,
therefore, be very uncomfortable place
in which to live. But in reality it is not
so, and for these reasons: In the dry
Western air the Precipitation from the
body evaporates SO rapidly as to keep the
skin cool, and none Of the heat given off
is held in by a screen of moist air; go
the body is kept cooler than it would be
in moist climate. But in the moister
atmosphere of the East evaporation is
slower, and the heat of the body does not
radiate SO rapidly into space. Hence the
perspiration gathers in great drops and
saturates the clothes, while pulses throb
and heads ache, till relief is sought by
tanning. And this tanning cools the
skin only because itincreases evaporation
by blowing air across its surface. This
also explains why warm, overcast,
muggy day is so oppressive. have rid.
den horseback all day over the dry
prairies of Montana, with the tempera-
ture above 100 degrees 10 the shade, and
have not suffered the slightest inconsen.
ience from the heat; while with the
temperature at go degrees in the humid
air of Washington, I have sat in my
Office 80 overcome as to be scarcely able
to work at sll.-AprI st. Nicholas