"Any rod, or bar, which is used in raising a weight, or surmounting a resistance, by being placed on a fulcrum, or prop, becomes a lever." -Comstock 1850

Simple Lever

"Any rod, or bar, which is used in raising a weight, or surmounting a resistance, by being placed on…

"...represents a simple pulley, with a single fixed wheel. In other forms of the machine, the wheel moves up and down with the weight." -Comstock 1850

Simple Pulley

"...represents a simple pulley, with a single fixed wheel. In other forms of the machine, the wheel…

"In the single moveable pulley, the same rope passes from the fixed point, A, to the power, P. It is evident here, that the weight, W, ten pounds, five pounds will be supported by one string, and five by the other. The power will then support twice its own weight." -Comstock 1850

Single Movable Pulley

"In the single moveable pulley, the same rope passes from the fixed point, A, to the power, P. It is…

A weight used to force a lure or bait to increase its rate of sink, anchoring ability, and/or casting distance.

Fishing Sinker

A weight used to force a lure or bait to increase its rate of sink, anchoring ability, and/or casting…

One of the commonest ways of determining the density of a solid body is to weight it first in air and then in water.

Specific Gravity of Solids

One of the commonest ways of determining the density of a solid body is to weight it first in air and…

An illustration of a price computing spring weighing machine.

Spring Weighing Machine

An illustration of a price computing spring weighing machine.

The steelyard is an instrument for weighing bodies by means of a single weight which can be hung at any point of a graduated arm.

Steelyard

The steelyard is an instrument for weighing bodies by means of a single weight which can be hung at…

"A Lever of the Third Kind is one in which the power is between the weight and the fulcrum." —Quackenbos 1859

Third Class Lever

"A Lever of the Third Kind is one in which the power is between the weight and the fulcrum." —Quackenbos…

In the third order of levers, the power is between the weight and the fulcrum.

Third Order of Lever

In the third order of levers, the power is between the weight and the fulcrum.

This experiment showed that every surface exposed to the atmosphere sustains a normal pressure equal to the weight of a column of mercury whose base is this surface and whose height is 30 inches.

Torricellian Experiment

This experiment showed that every surface exposed to the atmosphere sustains a normal pressure equal…

OP is a vector (directed quantity) showing the force by a weight acting on it at an angle of 20 degrees.

Vector Showing Force at Angle of 20 degrees

OP is a vector (directed quantity) showing the force by a weight acting on it at an angle of 20 degrees.

"Take a piece of ivory, or any other substance that will sink in water, and weigh it accurately in the usual manner; then suspend it by a thread, or hair, in the empty cup a, and balance it. Now pour water into the cup, and it will be found that the suspended body will lose a part of its weight, so that a certain number of grains must be taken from the opposite scale, in order to make the scales balance as before the water was poured in. The number of grains taken from the opposite scale, show the weight of a quantity of water equal to the bulk of the body so suspended." —Comstock, 1850

Water Weighing

"Take a piece of ivory, or any other substance that will sink in water, and weigh it accurately in the…

"The wedge is a movable inclined plane, and is used for moving a great weight a short distance. A common method is shown here." —Hallock 1905

Wedge

"The wedge is a movable inclined plane, and is used for moving a great weight a short distance. A common…

An illustration of a price computing weighing machine.

Price Computing Weighing Machine

An illustration of a price computing weighing machine.

An illustration of a price computing weighing machine using an even even balance and pendulum.

Price Computing Weighing Machine

An illustration of a price computing weighing machine using an even even balance and pendulum.

An illustration showing that 1 milliliter of water weighs the same as a 1 gram.

Weight Measures

An illustration showing that 1 milliliter of water weighs the same as a 1 gram.

Illustration comparing the fundamental units of measure ounces to grams and pounds to kilograms.

Comparison of Units of Weight

Illustration comparing the fundamental units of measure ounces to grams and pounds to kilograms.

Three cylindrical weights, suspended on ropes and pulleys.

Weights and Pulleys

Three cylindrical weights, suspended on ropes and pulleys.

"To change the direction, it is only necessary that the rope by which the weight is to be raised, should be carried in a line perpendicular to the axis of the machine, sto the place below where the weight lies, and there be let fall over a pulley." -Comstock 1850

Wheel and Axle

"To change the direction, it is only necessary that the rope by which the weight is to be raised, should…

"Considered as a lever, the fulcrum is at the common axis, while the arms of the lever are the radii of the wheel and of the axle. The usual arrangement is to take ac, the radius of the wheel, as the power arm, and bc , the radius of the axle, as the weight arm." -Avery 1895

Wheel and Axle

"Considered as a lever, the fulcrum is at the common axis, while the arms of the lever are the radii…

An illustration of a woman holding a scale with a man.

Woman Holding Scale with Man

An illustration of a woman holding a scale with a man.