The intersection of two planes is a straight line.

Intersecting Planes

The intersection of two planes is a straight line.

The intersection of two planes is a straight line.

Intersecting Planes

The intersection of two planes is a straight line.

The intersection of two planes is a straight line.

Intersecting Planes

The intersection of two planes is a straight line.

The intersection of two planes is a straight line.

Intersecting Planes

The intersection of two planes is a straight line.

Two intersecting planes on a third plane. "If two intersecting planes are each perpendicular to a third plane, their intersection is also perpendicular to that plane."

Intersecting Planes

Two intersecting planes on a third plane. "If two intersecting planes are each perpendicular to a third…

Illustration of two intersecting planes.

Intersecting Planes

Illustration of two intersecting planes.

Illustration of two parallel planes. "Two planes perpendicular to the same straight line are parallel."

Parallel Planes

Illustration of two parallel planes. "Two planes perpendicular to the same straight line are parallel."

Two parallel planes cut by a third plane.

Parallel Planes

Two parallel planes cut by a third plane.

Two parallel planes perpendicular to a line (AB).  "A straight line perpendicular to one of two parallel planes is perpendicular to the other also."

Parallel Planes

Two parallel planes perpendicular to a line (AB). "A straight line perpendicular to one of two parallel…

Three parallel planes cut by two lines.

Parallel Planes Cut By 2 Lines

Three parallel planes cut by two lines.

"If two intersecting lines are each parallel to a given plane, the plane of these lines is parallel to the given plane."

Parallel Planes

"If two intersecting lines are each parallel to a given plane, the plane of these lines is parallel…

"If two planes are perpendicular to each other, a line in one of them perpendicular to the intersection is perpendicular to the other."

Perpendicular Planes

"If two planes are perpendicular to each other, a line in one of them perpendicular to the intersection…

"The glass roof is commonly designed so as to form a uniform plane or slope from back to front in lean-to houses, and form center to sides in span-roofed houses. In some cases, however, the roof sashes are fitted up on the ridge-and-furrow principle invented by Sir Joseph Paxton." — Encyclopedia Britannica, 1893

Plant House

"The glass roof is commonly designed so as to form a uniform plane or slope from back to front in lean-to…

Draw the plan and elevation of a polygon of which the real shape and position in a given plane are known.

Draw Polygon

Draw the plan and elevation of a polygon of which the real shape and position in a given plane are known.

Illustration of a prism - a polyhedron of which two faces are equal polygons in parallel planes, and the other faces are parallelograms.

Prism

Illustration of a prism - a polyhedron of which two faces are equal polygons in parallel planes, and…

Illustration of the intersection of a prism and a plane.

Intersection of a Prism and a Plane

Illustration of the intersection of a prism and a plane.

"A proof-plane may be made by cementing a bronze cent or a disk of gilt paper to a thin insulating handle, as a glass tube or a vulcanite rod. Slide the disk of the proof-plane along the surface of the electrified body to be tested, and quickly bring it into contact with the knob of the gold-leaf electroscope, the leaves of which will diverge." — Avery, 1895

Hand with proof-plane

"A proof-plane may be made by cementing a bronze cent or a disk of gilt paper to a thin insulating handle,…

Pair of circular pulleys connected b a cord, showing the range of motion as arcs

Pulley

Pair of circular pulleys connected b a cord, showing the range of motion as arcs

"If a pyramid be cut by a plane, parallel to the base, so as to form two parts, the lower part is called the frustum of the pyramid." — Hallock, 1905

Pyramid

"If a pyramid be cut by a plane, parallel to the base, so as to form two parts, the lower part is called…

"A screw is a cylinder with a helical proection winding around its circumference. This helix is called the thread of the screw. The distance that a point of the helix is drawn back or advanced in the direction of the length of the screw during one turn is called the pitch of the screw." —Hallock 1905

Using a Screw to Raise Weight

"A screw is a cylinder with a helical proection winding around its circumference. This helix is called…

"A ratchet brace is a powerful instrument, and carries in itself the screw for obtaining the requisite pressure. Small holes can be drilled under a light pressure with rapid rotation on the part of the drill." — Encyclopedia Britannica, 1893

Ratchet Brace

"A ratchet brace is a powerful instrument, and carries in itself the screw for obtaining the requisite…

"From the surface of a plane mirror, parallel rays are reflected parallel; but the convex mirror causes parallel rays falling on its surface to diverge, by reflection." -Comstock 1850

Divergent Rays

"From the surface of a plane mirror, parallel rays are reflected parallel; but the convex mirror causes…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The lower part is known as the frustum.

Rectangular Pyramid Cut By Plane

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The lower…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top section has been removed and placed next to the lower section. The lower part is known as the frustum.

Rectangular Pyramid Cut By Plane

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top section has been removed and placed next to the lower section. The lower part is known as the frustum.

Rectangular Pyramid Cut By Plane

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The lower part is known as the frustum.

Rectangular Pyramid Cut By Plane

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The lower…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top section has been removed and the remaining section is known as the frustum of the pyramid. The hidden edges are shown in this illustration.

Frustum Of A Rectangular Pyramid

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top section has been removed and the remaining section is known as the frustum of the pyramid.

Frustum Of A Rectangular Pyramid

Illustration of a right rectangular pyramid that has been cut by a plane parallel to the base. The top…

Illustration of a right hollow rectangular pyramid that has been cut by a plane parallel to the base. The top section has been removed and the remaining section has been turned upside down. It is known as the frustum of the pyramid.

Frustum Of A Rectangular Pyramid

Illustration of a right hollow rectangular pyramid that has been cut by a plane parallel to the base.…

Illustration of a right hollow rectangular pyramid that has been cut by a plane parallel to the base. The top section has been removed and the remaining section has been turned upside down. It is known as the frustum of the pyramid. Hidden edges are shown in this drawing.

Frustum Of A Rectangular Pyramid

Illustration of a right hollow rectangular pyramid that has been cut by a plane parallel to the base.…

Illustration of a frustum of a pyramid having a rectangular base and a hole passing through the center of the frustum.

Frustum Of A Rectangular Pyramid With Hole

Illustration of a frustum of a pyramid having a rectangular base and a hole passing through the center…

Popcorn box that is in the shape of a frustum of a rectangular pyramid.

Popcorn Box Frustum Of A Rectangular Pyramid

Popcorn box that is in the shape of a frustum of a rectangular pyramid.

"Plane mirrors M revolve on an endless chain placed outside of the apparatus and alter the direction of the flashes after they pass into the dark arc on the landward side so as to cause the lenses L, L to repeat their flashes over the seaward are which requires strengthening. The condensing spherical mirror and mirror of unequal areas will also be found applicable in cases where the flashes do not require to sweep over the whole horizon." —The Encyclopedia Britannica, 1910

Repeating Light

"Plane mirrors M revolve on an endless chain placed outside of the apparatus and alter the direction…

"A series of planes as S—S are passed perpendicular to the axis of revolution, cutting out the circles shown on the end view. The points at which these circles cut the 'flat' are projected back as points on the curve." —French, 1911

Intersection of Surface of Revolution and Plane

"A series of planes as S—S are passed perpendicular to the axis of revolution, cutting out the…

Illustration showing a section of the rolling surfaces by a plane perpendicular to their straight line of contact.

Section of Rolling Surfaces

Illustration showing a section of the rolling surfaces by a plane perpendicular to their straight line…

A propeller airplane with rudder, elevator, and ailerons. The rudder stabilizes the plane vertical, and elevator adjusts the pressure exerted by the horizontal stabilizer for a downward force.

Airplane Rudder and Elevator

A propeller airplane with rudder, elevator, and ailerons. The rudder stabilizes the plane vertical,…

"That the screw is a modified inclined plane, may be shown by winding a triangular piece of paper around a cylinder." — Avery, 1895

Diagram of a screw

"That the screw is a modified inclined plane, may be shown by winding a triangular piece of paper around…

Illustration of a right septagonal/heptagonal pyramid, with hidden edges shown, that has been cut by a plane parallel to the base. The lower part is known as the frustum.

Septagonal/Heptagonal Pyramid Cut By Plane

Illustration of a right septagonal/heptagonal pyramid, with hidden edges shown, that has been cut by…

Illustration of a septagonal/heptagonal pyramid that has been cut by a plane parallel to the base. The top section has been removed and the remaining section is known as the frustum of the pyramid. The hidden edges are shown in this illustration.

Frustum Of A Septagonal/Heptagonal Pyramid

Illustration of a septagonal/heptagonal pyramid that has been cut by a plane parallel to the base. The…

"The smoothing plane." — Encyclopedia Britannica, 1893

Smoothing Plane

"The smoothing plane." — Encyclopedia Britannica, 1893

Illustration of two intersecting spheres. "The intersection of two spherical surfaces is the circumference of a circle whose plane is perpendicular to the line joining the centres of the surfaces and whose centre is in that line."

Intersecting Spheres

Illustration of two intersecting spheres. "The intersection of two spherical surfaces is the circumference…

In this illustration, "the driven surface of the slide coincides with the tangent to the spiral, the line of centres being from o through c to infinity and perpendicular to the direction of motion of the slide.""

Logarithmic Spiral Sector

In this illustration, "the driven surface of the slide coincides with the tangent to the spiral, the…

An illustration used to "square a cirleplane".

Square And Circle

An illustration used to "square a cirleplane".

Illustration of the intersection of a square pyramid and a plane.

Intersection of Square Pyramid and a Plane

Illustration of the intersection of a square pyramid and a plane.

Illustration of the intersection of a square pyramid and a plane.

Intersection of Square Pyramid and a Plane

Illustration of the intersection of a square pyramid and a plane.

"The wood-worker's main stand-by for boring is the stock or brace and set of bits." — Encyclopedia Britannica, 1893

Stock

"The wood-worker's main stand-by for boring is the stock or brace and set of bits." — Encyclopedia…

An early invention of the airplane, created by John Stringfellow in the mid-19th century.

Stringfellow's Flying Machine

An early invention of the airplane, created by John Stringfellow in the mid-19th century.

Illustration showing the motion of translation of two parallel motions.

Motion of Translation

Illustration showing the motion of translation of two parallel motions.

Illustration of the intersection of a triangular pyramid and a plane.

Intersection of Triangular Pyramid and a Plane

Illustration of the intersection of a triangular pyramid and a plane.

The desire to reproduce in wood these old stone ornaments led to the invention of a great number of plane bits, and the use of these bits naturally inspired tool makers to devise a plane in which many different bits could be employed.

Universal Hand Beader

The desire to reproduce in wood these old stone ornaments led to the invention of a great number of…

The desire to reproduce in wood these old stone ornaments led to the invention of a great number of plane bits, and the use of these bits naturally inspired tool makers to devise a plane in which many different bits could be employed. This one will plane wood into fifty-two different forms by simply changing the bits.

Universal Plane

The desire to reproduce in wood these old stone ornaments led to the invention of a great number of…

"The next simple mechanical power is the wedge. This instrument may be considered as two inclined planes, placed base to base." -Comstock 1850

Wedge

"The next simple mechanical power is the wedge. This instrument may be considered as two inclined planes,…

"A wedge is a triangular prism of hard material, fitted to be driven between objects that are to be separated, or into anything that is to be split." -Avery 1895

Wedge

"A wedge is a triangular prism of hard material, fitted to be driven between objects that are to be…

"[A wedge] is simply a movable inclined plane, or two such planes united a their bases." -Avery 1895

Wedge Splitting Wood

"[A wedge] is simply a movable inclined plane, or two such planes united a their bases." -Avery 1895

"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…

"This wedge is a movable inclined plane. Allows for raising great weights a short distance." —Quackenbos 1859

Inclined Plane Wedge

"This wedge is a movable inclined plane. Allows for raising great weights a short distance." —Quackenbos…