Illustration to show that if through any point in the bisector of an angle a line is drawn parallel…

Illustration showing 2 intersecting circles with a line drawn through each point of intersection terminated…

Illustration showing 2 circles with that touch each other and two lines drawn through the point of contact…

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

"When all of the positive plates are connected on one side, and all of the negative plates are connected…

Illustration used to construct a circle that shall pass through a given point and cut chords of a given…

Illustration showing that tangents drawn at the ends of any diameter are parallel to each other.

Each section is an ellipse. The surface is generated by an ellipse moving parallel to itself along two…

"An inclined plane is a slope, or flat surface, making an angle with a horizontal line...the force acts…

"An inclined plane is a slope, or flat surface, making an angle with a horizontal line...the force acts…

The parallel fret band is a pattern that is parallel in perspective that was found in a Roman mosaic…

"In railway engineering, the running together of parallel tracks into the space occupied by one, by…

"Hand-vices are used in the manner implied by their name, without being attached to a bench like the…

Illustration showing a line that remains parallel to a given line, and touches at one end a given circumference.

Illustration showing a line that moves so that its ends constantly touch two fixed lines which are perpendicular…

Illustration showing two straight lines in the same plane perpendicular to the same straight line are…

Illustration showing if a straight line is perpendicular to one of two parallel lines, it is perpendicular…

Illustration of two parallel lines with equal segments between them. Two parallel lines are everywhere…

Illustration showing that when three or more parallel lines intercept equal parts on one transversal,…

Illustration showing that if two parallel lines are cut by a transversal, then the alternate interior…

Illustration showing that when two straight lines in the same plane are cut by a transversal, if the…

Illustration showing that when two parallel lines are cut by a transversal, the exterior-interior angles…

Illustration showing that when two parallel lines are cut by a transversal, the two interior angles…

"a is the sphere, placed in half-holes on the axis bb, so that when its principal axis is parallel to…

"a is the sphere, placed in half-holes on the axis bb, so that when its principal axis is parallel to…

"Thus, were the rays falling on the mirror parallel, the focus would be at a' but in consequence of…

"The incident rays, a and b, being parallel before they reach the reflectors, are thrown off at unequal…

Illustration showing that if two tangents RP and RQ are drawn from a point R to a parabola, the line…

"Diagram of a multiple or parallel connection. When connected in this manner the voltage of the battery…

Figure showing battery cells connected in parallel, with all of the positive ends wired together, and…

Illustration showing two parallel vertical lines cut by a perpendicular line and a transversal. Congruent…

"Its mechanism may be understood by the means of the subjoined figure, B represents the end of the beam,…

"The English parallel vice is little used except for small work." — Encyclopedia Britannica, 1893

Diagram used to prove the theorem: "The opposite faces of a parallelopiped are equal and parallel."

"A parallelopipedon is a prism whose bases (ends) are parallelograms." —Hallock 1905

Diagram used to prove the theorem: "The rectangular parallelopipeds which have two dimensions in common…

Diagram used to prove the theorem: "The rectangular parallelopipeds are to each other as the product…

"If one of two parallels is perpendicular to a plane, the other is also."

Two straight lines, AB and CD, perpendicular to the same plane (MN) are parallel.

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

Two arrangements of pulley: crossed belt and uncrossed belt. The pulleys are constructed with two circles…

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

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