An illustration of a three triangles created with boats and a lighthouse. This is an example illustration used to fine the height of an object situated about the plane of observation, and its height above the plane.

Triangle with Lighthouse

An illustration of a three triangles created with boats and a lighthouse. This is an example illustration…

An ancient ship used by Greeks and Romans. The ship has three rows of oars on each side, with a man operating each oar.

An Athenian Trireme

An ancient ship used by Greeks and Romans. The ship has three rows of oars on each side, with a man…

A powerful small boat designed to pull or push larger ships

Small Tugboat

A powerful small boat designed to pull or push larger ships

A distinguished party aboard.

USS Despatch

A distinguished party aboard.

The Valley Farm. (Willy Lott's House.), a painting by John Constable.

The Valley Farm. (Willy Lott's House.)

The Valley Farm. (Willy Lott's House.), a painting by John Constable.

The sinking Varuna, a Union ship.

The Last Broadside of the Varuna

The sinking Varuna, a Union ship.

A tracked vehicle is a vehicle that runs on continuous tracks instead of wheels. The principal design advantages of tracked over wheeled vehicles are that they are in contact with a larger surface area than would generally be the case with a wheeled vehicle, and as a result exert a much lower force per unit area on the ground being traversed than a conventional wheeled vehicle of the same weight.

Traction Vehicle

A tracked vehicle is a vehicle that runs on continuous tracks instead of wheels. The principal design…

A canal in Venice, Italy.

A Canal in Venice

A canal in Venice, Italy.

The state barge of Venice, which was used in the ceremony of "Wedding the Adriatic."—Myers, 1905

State Barge of Venice

The state barge of Venice, which was used in the ceremony of "Wedding the Adriatic."—Myers, 1905

American steamship being chased by Spanish man-of-war.

The Spanish Man-of-War Tornado Chasing the American Steamer "Virginius"

American steamship being chased by Spanish man-of-war.

An illustration depicting the arrival of the Walloon settlers on Long Island.

Landing of the Walloons

An illustration depicting the arrival of the Walloon settlers on Long Island.

"The World's Fair at Chicago. Central portion of MacMonnies Fountain- effect of electric light."—E. Benjamin Andrews 1895

World's Fair

"The World's Fair at Chicago. Central portion of MacMonnies Fountain- effect of electric light."—E.…

A yawl, which is a two mast sailing craft.

Yawl

A yawl, which is a two mast sailing craft.