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

Anemometer

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

Illustration showing that the arc length can be found by multiplying the angle measure by the radius of the circle.

Model of Arc Length, Angle Measure, and Radius

Illustration showing that the arc length can be found by multiplying the angle measure by the radius…

A balance used for measuring weight.

Balance

A balance used for measuring weight.

"This is a very convenient and quite accurate method of determining specific gravity." — Ford, 1912

Beam balance

"This is a very convenient and quite accurate method of determining specific gravity." — Ford,…

"The most accurate method of determining the specific gravity of a mineral is by the use of a chemical balance. To one beam of the balance is suspended a wire basket which is so arranged that it can be immersed in a beaker of water. The basket is hung in the water and then counterbalanced by weights on the opposite pan of the balance. The mineral specimen to be tested, having been first weighed on the balance in the ordinary fashion, is now placed in the basket under the water and weighed again." — Ford, 1912

Chemical balance

"The most accurate method of determining the specific gravity of a mineral is by the use of a chemical…

An instrument for determining the weight or pressure of the atmosphere, and hence the changes of the weather, or height of any ascent.

Barometer

An instrument for determining the weight or pressure of the atmosphere, and hence the changes of the…

An illustration of Mance's method used to measure battery resistance.

Battery Resistance

An illustration of Mance's method used to measure battery resistance.

An illustration of Mance's method used to measure battery resistance.

Battery Resistance

An illustration of Mance's method used to measure battery resistance.

An illustration of the assisting and opposing method used to measure battery resistance.

Battery Resistance

An illustration of the assisting and opposing method used to measure battery resistance.

"A kind of compass for measuring the diameter of round bodies." — Williams, 1889

Calipers

"A kind of compass for measuring the diameter of round bodies." — Williams, 1889

"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…

Illustration comparing the fundamental units of measure quart and liter.

Comparison Of Units Of Capacity

Illustration comparing the fundamental units of measure quart and liter.

Illustration of a compass with one leg at point A on the line segment and the other at Point B.

Compass and Line

Illustration of a compass with one leg at point A on the line segment and the other at Point B.

Illustration of a compass with one leg at point O on the line segment and the other at Point M.

Compass and Line

Illustration of a compass with one leg at point O on the line segment and the other at Point M.

Illustration comparing the fundamental units of measure 1 cubic yard and 1 cubic meter.

Comparison Of Units Of Cubic Measure

Illustration comparing the fundamental units of measure 1 cubic yard and 1 cubic meter.

A graduated cylinder.

Graduated cylinder

A graduated cylinder.

"Dipping needle, a magnetic needle mounted on a horizontal support, and free to move in a vertical plane. The dipping needle is used to test the force of the earth's magnetism at different places on its surface." -Foster, 1921

Dipping Needle

"Dipping needle, a magnetic needle mounted on a horizontal support, and free to move in a vertical plane.…

"The simplest way of measuring a force is to use a dynamometer, of which the spring-balance is a familiar example. The dynamometer may be graduated in pounds, grams, poundals, or dynes." — Avery, 1895

Dynamometer

"The simplest way of measuring a force is to use a dynamometer, of which the spring-balance is a familiar…

An illustration of the foster method, used to measure electric current.

Foster's Method

An illustration of the foster method, used to measure electric current.

"For measuring the gas concentration, pressure and temperature, use may be made of an apparatus of the type shown [here]." —The Encyclopedia Britannica 1910

Apparatus for Measuring Gas Concentration Pressure and Temperature

"For measuring the gas concentration, pressure and temperature, use may be made of an apparatus of the…

An instrument used to measure the quantity of a rain which falls at a given place. They are which falls at a given place. They are variously constructed. A convenient form (shown in figure) consists of a cylindrical tube of copper, with a funnel at the top where the rain enters. Connected with the cylinder at the lowest part is a glass tube with an attached scale.

Rain Gauge

An instrument used to measure the quantity of a rain which falls at a given place. They are which falls…

"Wire-gage, a gage for measuring the thickness of wire and sheet-metal. It is usually a plate of steel having round the edge a series of notches of standard opening." -Whitney, 1911

Wire Gauge

"Wire-gage, a gage for measuring the thickness of wire and sheet-metal. It is usually a plate of steel…

An illustration of a girl measuring the heights of a boy and girl.

Girl Measuring Heights of Children

An illustration of a girl measuring the heights of a boy and girl.

The goniometer is an instrument for measuring the angles of crystals. Nicolaus Stena in 1669 determined the interfacial angles of quartz crystals by cutting sections perpendicular to the edges, he plane angles of the sections being then the angles between faces which are perpendicular to the sections.

Horizontal-Circle Goniometer

The goniometer is an instrument for measuring the angles of crystals. Nicolaus Stena in 1669 determined…

The goniometer is an instrument for measuring the angles of crystals. Nicolaus Stena in 1669 determined the interfacial angles of quartz crystals by cutting sections perpendicular to the edges, he plane angles of the sections being then the angles between faces which are perpendicular to the sections.

Vertical Circle Goniometer

The goniometer is an instrument for measuring the angles of crystals. Nicolaus Stena in 1669 determined…

"As generally made, a hydrometer of constant weight consists of a glass tube near the bottom of which are two bulbs. The lower and smaller bulb is loaded with mercury or shot. The tube and upper bulb contain air. The point to which it sinks when placed in water is marked zero. The tube is graduated, the scale being arbitrary, and varying with the purpose for which the instrument is intended." — Avery, 1895

Hydrometer of constant weight

"As generally made, a hydrometer of constant weight consists of a glass tube near the bottom of which…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lengths of lines a and b are the same. You would need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lengths of lines a and b are the same. You would need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lengths of lines a and b are the same. You would need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lengths of lines a and b are the same. You would need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lines are the same distance apart. You may need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lines are the same distance apart. You may need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lines are prolongations of the other lines. You may need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the lines are prolongations of the other lines. You may need to measure to be sure of your conclusion.

Optical Illusions

Illustration showing optical illusions. It is not always possible to trust the eye to be sure if the…

"Illustrating method of measuring insulation resistance." —Croft 1920

Measuring Insulation Resistance

"Illustrating method of measuring insulation resistance." —Croft 1920

"Testing the insulation resistance of a motor or generator from its winding to ground." —Croft 1920

Measure Insulation Resistance of Motor

"Testing the insulation resistance of a motor or generator from its winding to ground." —Croft…

A tool used to indicate whether a surface is level (horizontal) or plumb (vertical).

Spirit Level

A tool used to indicate whether a surface is level (horizontal) or plumb (vertical).

An illustration of the loss of charge method.

Loss of Charge Method

An illustration of the loss of charge method.

Three students use measuring tape to measure the school garden outside.

Measuring Garden

Three students use measuring tape to measure the school garden outside.

A man measuring the height of a boy against a wall.

Measruing height

A man measuring the height of a boy against a wall.

An illustration of two men drawing on the a sidewalk after measuring a distance.

Men Drawing on Sidewalk

An illustration of two men drawing on the a sidewalk after measuring a distance.

Micrometer

Micrometer

Micrometer

Wild mustard the proper size for spraying.

Wild mustard

Wild mustard the proper size for spraying.

A container used to measure a peck.

Peck

A container used to measure a peck.

Illustration of a child with 8 quarts and 1 peck. He is using the baskets to practice measuring. It can be used to write mathematics story problems involving addition, subtraction, money, measurement, and counting.

Child Measuring Using Pecks And Quarts

Illustration of a child with 8 quarts and 1 peck. He is using the baskets to practice measuring. It…

"From a cross piece, A, on a stout framework, a heavy block of wood, B, is suspended, in such a way as to move freely backward and forward. A ball fired into this block will drive it back to a distance proportioned to the ball's velocity. All other things being known, the ball's velocity can be discovered." —Quackenbos 1859

Ballistic Pendulum

"From a cross piece, A, on a stout framework, a heavy block of wood, B, is suspended, in such a way…

A device used for demonstrating the elastic properties of materials.

Physics demonstration

A device used for demonstrating the elastic properties of materials.

A piece of lead fastened to a line, and used to determine a perpendicular, and with a square, a horizontal line.

Plummet

A piece of lead fastened to a line, and used to determine a perpendicular, and with a square, a horizontal…

"A Rain Gauge is an instrument or contrivance for measuring the amount of rain which falls on a given surface."—(Charles Leonard-Stuart, 1911)

Rain Gauge

"A Rain Gauge is an instrument or contrivance for measuring the amount of rain which falls on a given…

"This is an instrument designed to measure the quantity of rain which falls at any given time and place." -Comstock 1850

Rain Gauge

"This is an instrument designed to measure the quantity of rain which falls at any given time and place."…

An instrument for measuring the quantity of rain that falls at any given place in a given time.

Rain-gauge

An instrument for measuring the quantity of rain that falls at any given place in a given time.

A decimeter rule.

Decimeter rule

A decimeter rule.

A straightedged strip, as of wood or metal, for drawing straight lines and measuring lengths.

Drawing Ruler

A straightedged strip, as of wood or metal, for drawing straight lines and measuring lengths.

A scale used for weighing milk.

Milk Scale

A scale used for weighing milk.

A system of ordered marks at fixed intervals used as a reference standard in measurement

Scientific Scale

A system of ordered marks at fixed intervals used as a reference standard in measurement

A patch of soil and grass which has cracked after having been worked too fine in the fall.

Cracks in the soil

A patch of soil and grass which has cracked after having been worked too fine in the fall.

Diagram used to prove the theorem: "A spherical angle is measured by the arc of a great circle described from its vertex as a ole and included between its sides (produced if necessary)."

Measure of a Spherical Angle

Diagram used to prove the theorem: "A spherical angle is measured by the arc of a great circle described…

Three spring-balances hooked together around a small ring.

Spring-balances

Three spring-balances hooked together around a small ring.

An active fire protection measure, consisting of a water supply system, providing adequate pressure and flowrate to a water distribution piping system, onto which fire sprinklers are connected.

Automatic Sprinkler

An active fire protection measure, consisting of a water supply system, providing adequate pressure…

Illustration comparing the fundamental units of measure 1 square yard and 1 square meter.

Comparison Of Units Of Square Measure

Illustration comparing the fundamental units of measure 1 square yard and 1 square meter.