New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1914-01-04
HOW THE RADIATOR HEATS

THE iratc fat dwcllcr, muiilcd Snugly in
huge bathrobo, seized "a papcrweight
and beat tattoo ON ,ho stew ~odiator.
The signal was readily interpreted 10y the
iamtor IN the basement as a hurry call for
more heat. and soon the man, throwing
aside his bathrobc, turned 90 his reading and
forgot that there was any such thing as heat
IN the world
What is this thing We call heat Does
the hot steam pipe pour out an invisible
fluid that warns the air IN the room, or IS
IL another mysterious force, like electricity,
that cannot be explained by human intclli-
gcnCc2
Neither. To explain heat it Is necessary to
imagine everything as composed Of mole
CulcS. which in turn are made up of atoms,
and this whole mass of particles IN violent
vibratorv motion. Increasing the motion OF
the atoms increases the temperature of the
mass. and decreasing this motion lowers the
temperature. When iron is very cold the
atoms and molecules move comparatively
slow. and when ii is whitchot the atoms
move So fast that they jostle one another
apart and soon begin to Follower one another,
and the melting iron flows like water.
Heat is derived from the sun, either from
the sun direct or from the suns energy
stored in coal or wood. But heat can also
bc derived from mechanical energy and from
electrical energy. Heat IS generated when
penny Is rubbed on the carpet, when a nail
Is struck by hammer, when two pieces Of
wood are rubbed together. BY rubbing two
pieces of ice together they may be melted,
though the temperature be far below freezing.
TT was generally believed, up to the nine
tccnth century, that heat was substance
devoid of weight and diffusod throughout
the great mass Of all things. This hypothcti-
cal substance was called Calorc. When
Davv proved that he could produce heat by
mechanical energy the old Calonc theory
was hurricdly abandoned.
Scientists are practically agreed that a
hot body differs from a cold body IN that
the very small particles, or molecules, OF
which II is composed are IN state OF rapid
to-and-fro motion or oscillation. Increasing
the temperature serves only TO increase the
violence of these molecular vibrations until
the BODY is melted down or evaporatcd.
When a body is deprived Of al It's heat the
oscillations cease entirely. If the sun S heat
should suddenly fail, the temperature OF the
earth would gradually drop to absolute
zero. or four hundred and fifty-ninc degrees
below zero, Fahrenheit. at which poln, the
molecules Of all materials are mo,ionlcsS.
Therefore. il becomes apparent that work,
or energy. must be communicated TO the
molecules before the oscillations can be pro-
duced. If q body is warmed at the fire, the
heat energy is transmitted to il. If two
pieces Of steel are heated by friction, work
is done on the molecules by the application
of power Energy can never be destroyed;
il can ONLY be changed in form. We say en-
ergv is lost when il is spread out 50 thin
thar il cannot be utilized.
These molecules that are in violent ag1-
tation are extremely minute, but have a
definite size and weight for each substance.
a moecule Of water, il has been figured, has
a diameter Of about one five-tcn-thousandths
Of an inch. Though these molecules are
very small in size, their velocity, even at
ordinary low temperatures, Is very great.
In air at the freezing point they osclllate
back and forth at the astonishing rate Of
fourteen hundred and seventy feet second.
The average length OF their path, between
oscillations. is about one northumberland
reimbursement Of an inch, and
the number Of these dancing molecules IN a
cubic inch of air is about one seXtilhon.
Each Of the molecules moves back and forth
. .---.6o o,oa5 oC11idinC with lis fellows