The Kenosha telegraph. [volume] (Kenosha, Wis.) 1860-1888, 1881-09-02

The idea of preserving the Superf1u-
Gus heat of summer for winter use is
one that has received attention from
philosophers and sages for many CEN
turtles. 1t is not generally suspected,
however, that the problem has been
we'll solved for some time-as far back
at least as the memory of man goes.
The editor of the Courier may not
have realized the fact, while toasting
his shins before a. glowing coal or
wood fire some of those pesky cold
days last winter, that it was merely
thesuperfuous( p heat of past summers
that he was utilizing. The idea of the
conservation of forces is one of the
sublimest doctrines that philosophy
has Investigated and proved beyond
any reasonable doubt. The applica-
ton of the doctrine to heat and cold is
one OF the most wonderful and inter-
esting things in physics. If a quantity
OF ice, at SO deg. Fahrenheit, is heated
over a slow fire. and, as fast as it melts,
the mixture Of ice and water is thor
Oughly stirred, a thermometer will
indicate no change of temperature. It
will remain constant at 80 until all of
the ice is melted and we will have in
stead of quantity of ice at 80 deg, a
quantity of water at that temperature.
Although the thermometer indicates
no change of temperature it cannot be
doubted that large amount of heat
has been absorbed in converting the
solid ice to the liquid water. The heat
thus absorbed has been termed latent
heat. Its exact amount can readily be
determined by experiments. If a.
pound of water at 80 be mixed with a
pound of water at 212, the result will be
two pounds of water with an exact
medium of temperature (92 plus PIP
divided by D or 122. The pound of
cold water is raised in temperature 80
degrees, the pound of warm water
loses 80 degrees of its heat. Every
degree of heat that the cold water
absorbs from the warm, the warm, of
course, loses; and as the amounts of
water are the same the results are as
above stated. Now, if pound of ice
at 80 be mixed with pound of boiling
water (212) the warm water will melt
the ice. 1t will not only melt it, but
the temperature of the mixture will be
81 degrees FIJI. What are we to learn
from this factP In the first place, the
warm water has lost (212 minus 51
161 degrees of its heat. The ice has
been converted into water, and it's tenn
perature has been raised 10 degrees.
If from the 161 degrees lost by the
warm water we subtract 10 degrees.
che remainder, LAP, will indicate the
amount OF heat necessary to convert a
pound of ice to a pound of water.
Problems of the amount of heat neces-
sary to convert ice at any temperature
to water of any temperature, with this
explanation and the above experiment
tested and proved, become easy. If,
for instance, 20 lbs. of ice at 10 above
zero is to be converted to water at 100,
p degrees will first be necessary to
raise each pound of the ice to the melt
ing point; 141 deg. will then be needed
to convert it to water without raising
its temperature and IS deg. to raise It'll
from 50 to 100. Twenty two deg. plus
l41 deg. plus IS, OF 232 deg, equals the
amount of heat necessary to produce
the requisite change in a pound of the
ice. Twenty pounds will require 20 |
times as much, or 1910 thermal units. |
In converting the water back to ice at |
10 the same amount of heat will be
absorbed. These results are believed |
to be of universal application. The |
question then arises what becomes of |