"A form of air-engine which was invented in 1816 by the Rev. R. Stirling is of special interest as embodying the earliest application of what is known as the "regenerative" principle, the principle namely that heat may be deposited by a substance at one stage of its action and taken up again at another stage but with little loss, and with a great resulting change in the substance's temperature at each of the two stages in the operation." —Encyclopedia Britannica, 1910

Stirling's Air Engine

"A form of air-engine which was invented in 1816 by the Rev. R. Stirling is of special interest as embodying…

"Bunsen's Burner, a form of gas burner especially adapted for heating, consisting of a tube, in which, by means of holes in the side, the gas becomes mixed with air before consumption, so that it gives a non-illuminating smokeless flame." -Vaughan, 1906

Bunsen Burner

"Bunsen's Burner, a form of gas burner especially adapted for heating, consisting of a tube, in which,…

"In Bunsen's instrument a test tube is sealed into and enclosed by an outer tube, the lower part of which, together with a tube leading from it to a narrow gauge, is filled with mercury."—Finley, 1917

Bunsen's Calorimeter

"In Bunsen's instrument a test tube is sealed into and enclosed by an outer tube, the lower part of…

An example of converting mechanical energy to heat.

Energy Conversion

An example of converting mechanical energy to heat.

An illustration showing the interchangeability of heat and mechanical energy.

Heat Conversion

An illustration showing the interchangeability of heat and mechanical energy.

"The expansion of solids by heat is clearly shown by the following experiment: m represents a ring of metal, through which, at the ordinary temperature, a small iron or copper ball, a, will pass freely, this ball being a little less than the diameter of the ring. If this ball be now heated by the flame of an alcohol lame, it will be come so far expanded by heat as no longer to pass through the ring." —Wells, 1857

Expansion of Solids

"The expansion of solids by heat is clearly shown by the following experiment: m represents a ring of…

An illustration of a small fire and smoke.

Small Fire and Smoke

An illustration of a small fire and smoke.

A flask being heated over an open flame, with a tube and jar attached.

Heated flask

A flask being heated over an open flame, with a tube and jar attached.

An illustration of a forge powered by a hand-bellows which forces air on glowing coals. A forge is a hearth, or a place for heating metals.

Forge

An illustration of a forge powered by a hand-bellows which forces air on glowing coals. A forge is a…

"Any arrangement in which heat is produced by burning fuel. It usually is a structure of iron or brick, lined with fire-brick to withstand intense heat." — Beach, 1909

Furnace

"Any arrangement in which heat is produced by burning fuel. It usually is a structure of iron or brick,…

That part of a gas fixture where the gas is burned as it escapes from one or more minute orifices.

Gas-burner

That part of a gas fixture where the gas is burned as it escapes from one or more minute orifices.

"Heat is radiated at C, which is placed at mirror A's focus. Mirror A catches some of the heat and reflects it across to mirror B which focuses the heat on D." —Quackenbos 1859

Reflection of Radiant Heat

"Heat is radiated at C, which is placed at mirror A's focus. Mirror A catches some of the heat and reflects…

"Place a bar of iron and a similar one of copper end to end so as to be heated equally by the flame of a lamp. Fasten small balls by wax to the under surfaces of the bars at eqiual distances apart. More balls will be melted from the copper than from the iron." -Avery 1895

Difference of Heat Transference Between Copper and Iron

"Place a bar of iron and a similar one of copper end to end so as to be heated equally by the flame…

Electric heating is any process in which electrical energy is converted to heat. Common applications include heating of buildings, cooking, and industrial processes. An electric heater is an electrical appliance that converts electrical energy into heat. The heating element inside every electric heater is simply an electrical resistor, and works on the principle of Joule heating: an electric current through a resistor converts electrical energy into heat energy.

Electric Heater Case

Electric heating is any process in which electrical energy is converted to heat. Common applications…

A vacuum steam heating system from the late 19th century.

Heating System

A vacuum steam heating system from the late 19th century.

A heating system spread throughout a two story home.

Heating System

A heating system spread throughout a two story home.

"Hero's Machine. The generation of steam from water by the application of heat, and the mechanical force produced by this means, appear to have been understood at a very remote period; but their application to machinery devoted to the purposes of locomotion, is a discovery of recent date. The ingenious contrivances of early discoverers were devoted to objects of minor importance, as those of raising water and propelling smoke upwards." —Comstock, 1850

Hero's Machine

"Hero's Machine. The generation of steam from water by the application of heat, and the mechanical force…

Bernieres Immense Burning Glass is an illustration found in an illustrated journal The "Wonders of Heat" by Achille Cazin. This drawing shows the phenomenon of burning glass to produce heat.

Bernieres Immense Burning Glass

Bernieres Immense Burning Glass is an illustration found in an illustrated journal The "Wonders of Heat"…

"Joule's experiment on the mechanical equivalent of heat, in which he caused paddlewheels to rotate in a vessel of water by means of falling weights W." -Hawkins, 1917

Joule's Experiment

"Joule's experiment on the mechanical equivalent of heat, in which he caused paddlewheels to rotate…

"With a lamp chimney or other large glass tube, a perforated cork, two pieces of glass tubing 4 and 15 inches long respectively, a bit of rubber tubing, a small lamp or candle, and two coverless crayon boxes, arrange apparatus as shown." — Avery, 1895

Lamp chimney and candle

"With a lamp chimney or other large glass tube, a perforated cork, two pieces of glass tubing 4 and…

During the day the land near the coast becomes warmer than the sea. An ascending current, therefore, rises over the land, and a breeze, called the <em>sea breeze</em>, sets in from the sea, At night the land, from its more rapid cooling, soon becomes colder than the water; the ascending current then rises from the water, and a breeze, called <em>land breeze</em>, sets in from the land.

Land and Sea Breezes

During the day the land near the coast becomes warmer than the sea. An ascending current, therefore,…

"Lenz's apparatus for measuring the heat given off by an electric current." -Hawkins, 1917

Lenz's Apparatus

"Lenz's apparatus for measuring the heat given off by an electric current." -Hawkins, 1917

A snow melting machine is a type of snow removal machine employed to melt snow as a means of snow removal.

Snow Melting Machine

A snow melting machine is a type of snow removal machine employed to melt snow as a means of snow removal.

An illustration of a man watching a tea kettle steaming in a fireplace.

Man Watching Tea Kettle

An illustration of a man watching a tea kettle steaming in a fireplace.

"Suppose a red hot ball to be placed in the principle focus of the mirror, a, the rays of heat and light proceeding from it will be reflected in the parallel lines 1, 2, 3 etc." -Comstock 1850

Reflection of Heat Using Concave Mirrors

"Suppose a red hot ball to be placed in the principle focus of the mirror, a, the rays of heat and light…

Winds are masses of air in motion. They resemble the currents in the ocean, and result from the same causes-differences of density caused by differences of temperature.

Origin of Winds

Winds are masses of air in motion. They resemble the currents in the ocean, and result from the same…

"As temperature elevates, the metal bar being tested expands accordingly and the dial measures the expansive power per degree of heat." &mdash;Quackenbos 1859

Pyrometer

"As temperature elevates, the metal bar being tested expands accordingly and the dial measures the expansive…

"Summer and Winter rays.&mdash;Let us suppose that the rays falling perpendicularly on a given extent of surface, impart to it a certain degree of heat, then it is obvious, that if the same number of rays be spread over twice that extent of surface, their heating power would be diminished in proportion, and that only half of the heat would be imparted. This is the effect produced by the Sun's rays in the Winter. They fall so obliquely on the Earth, as to occupy nearly double the space that the same number of rays do in the Summer." &mdash;Comstock, 1850

Rays

"Summer and Winter rays.—Let us suppose that the rays falling perpendicularly on a given extent…

The effect of heat on red blood cells up to 50-60 degrees C. (120-140 degrees F.) is to cause the formation of a number of bud-like processes.

Effect of Heat on Red Blood Cells

The effect of heat on red blood cells up to 50-60 degrees C. (120-140 degrees F.) is to cause the formation…

"About two feet away from an air thermometer, place an inverted flower pot. Midway between the two, place a board or glass screen that reaches from the table to a height of several inches above teh bulb of the air theremometer. Upon the flower pot, place a very hot brick. Notice that the heat of the brick has little effect upon the thermometer. Then hold a sheet of tin plate over the screen so that energy radianted obliquely upward from the brick may be reflected obliquely downward toward the thermometer. By properly adjusting the position of the reflector, the thermometer may be quickly affected." -Avery 1895

Heat Reflection

"About two feet away from an air thermometer, place an inverted flower pot. Midway between the two,…

This furnace is used to purify a gold concentrate. The gold concentrates, if non-pyritic, are treated in grinding pans in the bottom of which mercury is placed. The amalgam (mercury alloy), after squeezing out the excess mercury, is heated in the retort, to distil (separate) off the rest and leave the gold, which is then melted and cast into bars of gold bullion of varying fineness.

Retort Furnace for Gold Bullion

This furnace is used to purify a gold concentrate. The gold concentrates, if non-pyritic, are treated…

A large metal container used to heat and boil water in.

Samovar

A large metal container used to heat and boil water in.

During the prevalence of the simoom, particles of fine sand are carried into the atmosphere and obscure the light of the sun. Becoming intensely heated, these particles, by their radiation, increase the temperature of the air, which sometimes rises as high as 120 degrees or 130 degrees Fahr. When powerful winds prevail, dense clouds of sand are carried about in the atmosphere, producing the so-called sand storms. The sand-drifts which are thus formed constantly change their position.

Sand Storm in the Desert

During the prevalence of the simoom, particles of fine sand are carried into the atmosphere and obscure…

"A small covered brazier of glazed earthenware, used in Italy." -Whitney, 1911

Scaldino

"A small covered brazier of glazed earthenware, used in Italy." -Whitney, 1911

This illustration shows a standard Lowe water gas apparatus.

Standard Lowe Water Gas Apparatus

This illustration shows a standard Lowe water gas apparatus.

"Tyndall's experiment illustrating the production of heat by friction. The wheel is rotated and heat is produced [by friction] that heats the water in the end of the brass tube, which causes the water to boil, producing steam which pops off the cork." -Hawkins, 1917

Tyndall's Experiment

"Tyndall's experiment illustrating the production of heat by friction. The wheel is rotated and heat…

A food steamer or steam cooker is a kitchen appliance used to prepare various foods in a sealed vessel that limits the escape of air or liquids below a preset pressure.

Steam Cooking Utensil

A food steamer or steam cooker is a kitchen appliance used to prepare various foods in a sealed vessel…

"The vacuum-pan is in universal use in all European sugar-refineries, and in all well-provided sugar-plantations. It is generally made of copper, of a spherical form, and from six to nine feet in diameter. The bottom is double, leaving a space of an inch or two for the admission of steam between the two bottoms, and there is generally a long coiled copper pipe of three or four inches diameter above the inner bottom, so as to still further increase the amount of heating surface." &mdash; Chambers, 1881

Vacuum-pan

"The vacuum-pan is in universal use in all European sugar-refineries, and in all well-provided sugar-plantations.…

"Diagram indicating one explanation which has been advanced for light and heat waves generated by the movement of an electron around its orbit in a molecule and by the simultaneous movement of the molecule." &mdash;Croft 1917

Light Waves

"Diagram indicating one explanation which has been advanced for light and heat waves generated by the…