"The air passages of the lungs." — Richardson, 1906

Air Passages

"The air passages of the lungs." — Richardson, 1906

"A piston and rod shown with attached weight. The valve, A, can be opened and closed as needed so that the piston can be moved." —Hallock 1905

Piston and Rod

"A piston and rod shown with attached weight. The valve, A, can be opened and closed as needed so that…

"The air pump is an instrument for removing air from a given space. A closed vessel R is called the receiver, and the space that it encloses is that from which it is desired to remove the air. It is usually made of glass, and the edges are ground so as to be perfectly air-tight. When made in the form shown, it is called a bell-jar receiver." — Hallock, 1905

Air Pump

"The air pump is an instrument for removing air from a given space. A closed vessel R is called the…

"The air pump is an instrument for removing air from a given space. A closed vessel R is called the receiver, and the space that it encloses is that from which it is desired to remove the air. It is usually made of glass, and the edges are ground so as to be perfectly air-tight. When made in the form shown, it is called a bell-jar receiver." — Hallock, 1905

Air Pump

"The air pump is an instrument for removing air from a given space. A closed vessel R is called the…

"The air pump is an engine by which the air can be pumped out of a vessel, or withdrawn from it. The vessel so exhausted, is called a receive, and the space thus left in the vessel, after withdrawing the air, is called a vacuum. The principles on which the air pump is constructed are readily understood, and are the same in all instruments of this kind, though the form of the instrument itself is often considerably modified. Let R be a glass vessel, or receiver, closed at the top, and open at the bottom, standing on a perfectly smooth surface, which is called the plate of the air pump. Through thie plate is an aperture, which communicates with the inside of the receiver, and the barrel of the pump. The piston rod works air tight through the barrel. At the extremity of the barrel, there is a valve which opens upwards, and is closed as the piston rises." —Comstock, 1850

Air Pump

"The air pump is an engine by which the air can be pumped out of a vessel, or withdrawn from it. The…

"The piston rods are furnished with racks, or teeth, and are worked by the toothed wheel a, which is turned backwards and forwards, by the lever and handle b. The exhaustion pipe c, leads to the plate on which the receiver stants. The valves v, n, u, and m, all open upwards." —Comstock, 1850

Air Pump

"The piston rods are furnished with racks, or teeth, and are worked by the toothed wheel a, which is…

"The air pump is an instrument for removing a gas from a closed vessel, the essential parts are shown." -Avery 1895

Air Pump

"The air pump is an instrument for removing a gas from a closed vessel, the essential parts are shown."…

"Crank M raises and lowers the two pistons C and D. The valves allow only for air to be removed from chamber J with a cutoff valve at K. The mercury filled barometer L measures the pressure in J." —Quackenbos 1859

Double Barrel Air Pump

"Crank M raises and lowers the two pistons C and D. The valves allow only for air to be removed from…

Air pump used for taking the air out of a vessel.

Single Barrel Air Pump

Air pump used for taking the air out of a vessel.

"<em>A</em>, epithelial lining wall; <em>B</em>, partition between two adjacent sacs, in which run capillaries; <em>C</em>, fibers of elastic tissues." &mdash; Blaisedell, 1904

Diagrammatic view of an air sac

"A, epithelial lining wall; B, partition between two adjacent sacs, in which run capillaries;…

An airship or dirigible is an aircraft that can be steered and propelled through the air using rudders and propellers or other thrust. Unlike other aerodynamic aircraft such as fixed-wing aircraft and helicopters, which produce lift by moving a wing through the air, aerostatics aircraft, such as airships and hot air balloons, stay aloft by filling a large cavity, such as a balloon, with a lifting gas.

Cable Air Ship

An airship or dirigible is an aircraft that can be steered and propelled through the air using rudders…

"A motor employing the elastic force of air expanded by heat, or air compressed by means of another and separate motor, which is generally a steam engine."-Whitney, 1902

Air-engine

"A motor employing the elastic force of air expanded by heat, or air compressed by means of another…

"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." &mdash;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…

"An apparatus for the exhaustion, compression, or transmission of air."-Whitney, 1902

Air-pump

"An apparatus for the exhaustion, compression, or transmission of air."-Whitney, 1902

"A machine for remobing air out of any given vessel, or forcing it in." &mdash; Williams, 1889

Air-pump

"A machine for remobing air out of any given vessel, or forcing it in." — Williams, 1889

"The general scheme of Geisler's pump is shown here. A and B are pear-shaped glass vessels connected by a long narrow india-rubber tube, which must be sufficiently strong in the body (or strengthened by a linen coating) to stand an outward pressure of 1 to 1.5 atmospheres. A terminates below in a narrow vertical tube c, which is a few inched longer than the height of the barometer, and to the lower end of this tube the india-rubber tube is attached which connects A with B. To the upper end of A is soldered a glass two-way stop-cock, by turning which the vessel A can either be made to communicate through s and a hole in the hollow cock with the vessel to be exhausted." &mdash;The Encyclopedia Britannica, 1903

Air-Pump

"The general scheme of Geisler's pump is shown here. A and B are pear-shaped glass vessels connected…

"The general scheme of Geisler's pump is shown here. A and B are pear-shaped glass vessels connected by a long narrow india-rubber tube, which must be sufficiently strong in the body (or strengthened by a linen coating) to stand an outward pressure of 1 to 1.5 atmospheres. A terminates below in a narrow vertical tube c, which is a few inched longer than the height of the barometer, and to the lower end of this tube the india-rubber tube is attached which connects A with B. To the upper end of A is soldered a glass two-way stop-cock, by turning which the vessel A can either be made to communicate through s and a hole in the hollow cock with the vessel to be exhausted." &mdash;The Encyclopedia Britannica, 1903

Air-Pump

"The general scheme of Geisler's pump is shown here. A and B are pear-shaped glass vessels connected…

"This was invented in 1865 by H. Sprengel. The instrument, in its original (simplest) form, consists of a vertical capillary glass tube a of about 1 mm. bore, provided with a lateral branch b near its upper end, which latter, by an india-rubber join governable by a screw-clamp, communicates with a funnel. The lower end is bent into the shape of a hook, and dips into a pneumatic trough. The vessel to be exhausted is attached to b, and, in order to extract its gas contents, a properly regulated stream of mercury is allowed to fall through the vertical tube." &mdash;The Encyclopedia Britannica, 1903

Air-Pump

"This was invented in 1865 by H. Sprengel. The instrument, in its original (simplest) form, consists…

"Device used for measuring the velocity of the wind." -Comstock 1850

Anemometer

"Device used for measuring the velocity of the wind." -Comstock 1850

A hot air balloon used for transportation.

Balloon

A hot air balloon used for transportation.

"...being merely a tube of glass, nearly filled with mercury, with its lower end placed in a dish of the same fluid, and the upper end furnished with a scale, to measure the height of the mercury." -Comstock 1850

Barometer

"...being merely a tube of glass, nearly filled with mercury, with its lower end placed in a dish of…

Water beetles carry air bubbles under their abdomens, which provides an air supply. Water beetle larvae dwell at the bottom of ponds.

Water Beetle Larva

Water beetles carry air bubbles under their abdomens, which provides an air supply. Water beetle larvae…

An instrument by which a current of air or gas is driven through the flame of a lamp, candle, or gas jet, and that flame directed upon a mineral substance, to fure or vitrify it, an instense head being created by the rapid supply of oxygen and the concentration of the flame upon a small area.

Blowpipe

An instrument by which a current of air or gas is driven through the flame of a lamp, candle, or gas…

A conveyance braking system actuated by compressed air. Modern trains rely upon a fail-safe air brake system

Air Brake

A conveyance braking system actuated by compressed air. Modern trains rely upon a fail-safe air brake…

"An air thermometer consists essentially of a large glass bulb at the upper end of a tube of small but uniform bore, the lower end of which dips into colored water." &mdash; Avery, 1895

Glass bulb

"An air thermometer consists essentially of a large glass bulb at the upper end of a tube of small but…

This blower has a drum consisting of two side plates and a series of partition plates curved in a cross section. The fan is usually long in relation to the diameter.

Centrifugal Blower

This blower has a drum consisting of two side plates and a series of partition plates curved in a cross…

This chair features a mechanical system that spins an idler gear while the user is rocking back and forth to propel a fan located above the users headrest

Automatic Fan for Rocking Chair

This chair features a mechanical system that spins an idler gear while the user is rocking back and…

The Common Guillemot (<i>Uria troile</i>) is a member of the auk family. It breeds on all rocky coasts of the North Atlantic. The bill is long, straight, and strong, the wings and tail short. In spring, the upper surface of the body is brownish black, the under white, save for the dark throat; in winter, the throat becomes white or mottled. All guillemots lay a single pear-shaped on the ledge of a sea-cliff. They make no nest whatever, and large colonies brood in company.

Common Guillemot

The Common Guillemot (Uria troile) is a member of the auk family. It breeds on all rocky coasts of the…

"The compressed air manometer consists of a strong graduated glass tube of uniform narrow bore, closed at the top and fixed hermetically into the neck of a wide iron cylinder. The tube contains dry air, and its lower end dips below the surface of mercury contained in the cylinder. Attached to the side of the cylinder is a tube A, with a stop-cock, to afford communication with the vessel the pressure in which is to be measured. When the manometer is attached to the vessel containing compressed gas the mercury rises in the glass tube till the pressure of the air confined in the tube plus the height of the mercury column above the level of the mercury in the cylinder is equal to the pressure on the surface of mercury in the cylinder." &mdash;The Encyclopedia Britannica, 1903

Compressed Air Manometer

"The compressed air manometer consists of a strong graduated glass tube of uniform narrow bore, closed…

"Let P be a piston, fitted, air-tight, to the cylinder AB. As the piston is driven down, the air, unable to escape, is compressed; as it is drawn back, the air expands." &mdash;Quackenbos 1859

Compressibility of Air

"Let P be a piston, fitted, air-tight, to the cylinder AB. As the piston is driven down, the air, unable…

"If the strong tube, or barrel, be smooth, and equal on the inside, and there be fitted to it the solid piston, or plug a, so as to work up and down, air tight, by the handle b, the air in the barrel may be compressed into a space a hundred times less than its usual bulk. Indeed, if the vessel be of sufficient strength, and the force employed sufficiently great, its bulk may be lessened a thousand times, or in any proportion, according to the force employed; and if kept in this state for years, it will regain its former bulk the instant the pressure is removed." &mdash;Comstock, 1850

Compression Experiment

"If the strong tube, or barrel, be smooth, and equal on the inside, and there be fitted to it the solid…

"For many purposes compressed air is preferable to steam or other gas for use as a motive power. In such cases air compressors are used to compress air. These are made in many forms, but the most common one is to place a cylinder, called the air cylinder, in front of the crosshead of a steam engine, so that the piston of the air cylinder can be driven by attaching its piston rod to the crosshead in a manner similar to a steam pump." &mdash;Hallock 1905

Air Compressor

"For many purposes compressed air is preferable to steam or other gas for use as a motive power. In…

"The operation of the condenser is the reverse of that of the air pump, and is a much more simple machine. The air pump, will deprive a vessel of its ordinary quantity of air. The condenser, on the contrary, will double or treble the ordinary quantity of air in a close vessel according to the force employed. This instrument consists of a pump barrel and piston, a, a stop-cock b, and the vessel c furnished with a valve opening downwards. The orifice d is to admit the air, when the piston is drawn up to the top of the barrel." &mdash;Comstock, 1850

Condenser

"The operation of the condenser is the reverse of that of the air pump, and is a much more simple machine.…

"Air is pumped down through shaft A through a downward opening valve into a given chamber. Connector V is able to be screwed into any strong vessel where it is desired to condense air." &mdash;Quackenbos 1859

Condenser

"Air is pumped down through shaft A through a downward opening valve into a given chamber. Connector…

"The metal cut away near the center reduces the weight and provides passages for air circulation." &mdash; Hawkins, 1917

Solid core disk

"The metal cut away near the center reduces the weight and provides passages for air circulation." —…

"Suppose a b c to represent a portion of the earth's surface a being towards the north pole, c towards the south pole...The currents of air are supposed to pass in the direction of the arrows. the wind, therefore, for a to b would blow on the surface of the earth, from north to south, while from e to a, the upper current would pass from south to north, untl it came to a, when it would change is direction towards the south." -Comstock 1850

Opposite Currents of Air

"Suppose a b c to represent a portion of the earth's surface a being towards the north pole, c towards…

"The diving dress envelops the whole body of the diver, the upper portion a being the "helmet," the intermediate portion b the "breast-plate," and the lower portion c the "dress." The hose by which the air is supplied is shown at d, and e is the "life" or "signal" line, which is attached to the diver's waist, and by which he makes signals and is hauled to the surface. The water-proof material of which the dress is made is very generally sheet india-rubber covered on both sides with tanned twill to protect the india-rubber from injury." &mdash; Encyclopedia Britannica, 1893

Diving Dress

"The diving dress envelops the whole body of the diver, the upper portion a being the "helmet," the…

A storm composed of sand. It occurs when the air over the sand becomes hot, and rises. The differences in air pressure and temperature allow the cooler winds to rush in.

Dust Storm

A storm composed of sand. It occurs when the air over the sand becomes hot, and rises. The differences…

"Various methods have been devised for measuring electrostatic quantity, one of the simplest of which is with the Kinnersley electrical air-thermometer. When a spark passes between the balls within the larger tube, the confined air is expanded, and the liquid column in the smaller communicating tube rises, and thus approximately indicates the quantity of the charge." &mdash; Avery, 1895

Kinnersley electrical air-thermometer

"Various methods have been devised for measuring electrostatic quantity, one of the simplest of which…

"Remove the air from a high glass tube by means of an instrument called the air-pump... Then... drop a feather and a cent simultaneously, and they will reach the bottom at precisely the same instant. Let in the air and drop them, and the feather will be several seconds longer than the cent in reaching the bottom." &mdash;Quackenbos 1859

Two Objects Falling in a Vacuum

"Remove the air from a high glass tube by means of an instrument called the air-pump... Then... drop…

"Pass the tube of an air thermometer or of an inverted mercury thermometer through a cork in the neck of a funnel. Cover the thermometer bulb to the depth of about half an inch with water. Upon the water, pour a little sulphuric ether and ignite it. The thermometer below will scarcely be affected, although the water above may be boiling. Stir the water and note the prompt movement of the thermometer index..." -Avery 1895

Funnel with Inverted Mercury Thermometer

"Pass the tube of an air thermometer or of an inverted mercury thermometer through a cork in the neck…

A carpenter's tool used for guaging to a width.

Gauge

A carpenter's tool used for guaging to a width.

A girl standing with her hands straight out in the air.

Girl Standing

A girl standing with her hands straight out in the air.

"Tetraodon have a remarkable power of inflating their bodies by filling their stomachs with air, the stomach being extremely dilatable, and assuming a globular form when distended, whence they have received the name Globe Fish, whilst from the spines, which stand out in all directions, like those of a hedgehog when rolled up, as if for defence of the inflated body, some of them have been designated Porcupine Fish." &mdash; Chambers' Encyclopedia, 1875

Globefish

"Tetraodon have a remarkable power of inflating their bodies by filling their stomachs with air, the…

A group of people pointing at a hot air balloon in the distance.

Hot air balloon

A group of people pointing at a hot air balloon in the distance.

"The hydraulic ram uses alternating water pressure, air pressure, and suction to provide a steady stream of water through the delivery pipe, e." &mdash;Hallock 1905

Hydraulic Water Ram

"The hydraulic ram uses alternating water pressure, air pressure, and suction to provide a steady stream…

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,…

"Vertical section of the leaf of Potamogeton or Pondweed, showing air cavities or lecunae l, and parenehymatous cells p, with granules." &mdash; Encyclopedia Britanica, 1893

Pondweed Leaf

"Vertical section of the leaf of Potamogeton or Pondweed, showing air cavities or lecunae l, and parenehymatous…

"A labratory liquid air machine used by Thomson and Joule used to cool hydrogen from a gaseous state to a liquid state." &mdash;The Encyclopedia Britannica 1910

Liquid Air Machine

"A labratory liquid air machine used by Thomson and Joule used to cool hydrogen from a gaseous state…

"<em>A</em>, an air sac; <em>B</em>, an air sac cut open; <em>C</em>, capillary network over an air sac; <em>D</em>, branch of pulmonary artery; <em>E</em>, branch of pulmonary vein; <em>F</em>, bronchial tube." &mdash; Blaisedell, 1904

Lobule of the lung

"A, an air sac; B, an air sac cut open; C, capillary network over an air…

"Grease the edges to make more sure of a tight joint, fit the hemispheres to each other, and exhaust the air with a pump. Close the stopcock, remove the hemispheres from the pump, attach the second handle, and, holding the hemispheres in different positions, try to pull them apart. When you are sure that the pressure that holds them together is exerted inall directions, place them under the receiver of the air pump, and exhaust the air from around them. The pressure seems to be removed, for the hemispheres fall apart of their own weight." -Avery 1895

Magdeburg Hemispheres

"Grease the edges to make more sure of a tight joint, fit the hemispheres to each other, and exhaust…

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…

"[This illustration] shows the path of a stone thrown obliquely from the hand. The propelling force sends it in a straight line to A, and would take it on in the same direction to B, were it not that, as soon as its velocity becomes sufficiently diminished, gravity and the air's resistance give it a circular motion to C, and finally bring it to the earth at D." &mdash;Quackenbos 1859

Projectile Motion of a Stone

"[This illustration] shows the path of a stone thrown obliquely from the hand. The propelling force…

"Let a represent a, b water, and c a piece of glass. The ray d, striking each medium in a perpendicular direction." -Comstock 1850

Refraction, air, water, glass

"Let a represent a, b water, and c a piece of glass. The ray d, striking each medium in a perpendicular…

"Thus, when erher waves that constitute light are transmitted through glass, they are hindered by the molecules of the glass, and impart some of their motion to those molecules' i.e., a part of the light is absorbed. When a beam of light, as represented by ABC moves forward in the air, the wave-front, MN, continues parallel to itself and moves forward in a straight line. As the wave front advances, A strikes the glass first, and is retarted, the retardation of B and C later change the direction of the rays." -Avery 1895

Explanation of Refraction

"Thus, when erher waves that constitute light are transmitted through glass, they are hindered by the…

"LA represents a ray of light propagated in air, falling obliquely upon the surface of the water at A, and deviated by the water from AE to AK." -Avery 1895

Refraction of Light Between Air and Water

"LA represents a ray of light propagated in air, falling obliquely upon the surface of the water at…

"If the ray passes in the opposite direction, i.e., from water into air, the process is the reverse of that just indicated. Let KA represent the incident ray." -Avery 1895

Refraction of Light Between Water and Air

"If the ray passes in the opposite direction, i.e., from water into air, the process is the reverse…

"Diagram to illustrate a root-hair (h) in the soil, and its relation to the soil-particles, the capillary film of water (w), and the air spaces (a); e, epidermal cell of the root, of which the root-hair is an out-growth, or branch." -Gager, 1916

Roots in Soil

"Diagram to illustrate a root-hair (h) in the soil, and its relation to the soil-particles, the capillary…

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…

"...represents a Savart bell and resonator. The length of the resonant air-column is changed by means of the moveable bottom of the resonator, which is to be adjusted by trial for resonant effect." -Avery 1895

Savart Bell and Resonator

"...represents a Savart bell and resonator. The length of the resonant air-column is changed by means…