"Until hard rock is reached the sides of the excavation are supported temporarily by a lining"—Finley,…

Four different types of forms or shapes: right triangle, isosceles triangle, rectangle, and circle.

"The Flanch is formed of a segment of a circle placed on the side of the shield. It is always borne…

"The Rustre differs from the mascle in that the perforation of the device is circular and not throughout."—Aveling,…

"An instrument for throwing stones or bullets, consisting of a strap and two strings attached to it.…

An illustration in flattening the sphere using Gore method by creating cylinder sections with equal…

An illustration of a development of sphere using Zone method by creating sections of rolled out cones.

An 8-inch sphere cut by parallel planes, one 2 inches from center and the other 6 inches from center.…

A sphere with arcs and poles. "The distance of all points in the circumference of a circle of a sphere…

"Every section of a sphere made by a plane is a circle."

Diagram used to prove the theorem: "All points in the circumference of a circle of a sphere are equally…

An illustration of a sphere cut into polygons as bases with their vertices at the center of sphere.

An illustration of a sphere inside of a cylinder with radius/diameter labeled. Illustration for showing…

An illustration of a sphere showing diameter, arcs, and circles. A sphere is a solid bounded by a curved…

An illustration of a sphere showing diameter, arcs, and circles. A sphere is a solid bounded by a curved…

Illustration of a sphere generated by the revolution of a semicircle ACB about its diameter AB as an…

Illustration of a sphere with a tangent plane. "A plane perpendicular to a radius at its extremity is…

Illustration of a sphere with a tangent plane. "A plane perpendicular to a radius at its extremity is…

Illustration of a sphere with a polyhedral angle whose vertex is at the center of the sphere and whose…

A sphere with quadrants and poles. "A point on the surface of a sphere, which is at the distance of…

An illustration of a sphere showing a radius of 1 foot. Illustration could be used for calculating volume.

A wooden hollow sphere created by using a lathe and wooden templet at a desired diameter.

An illustration of a zone of a sphere. A zone occurs when a sphere is cut by parallel planes that are…

An illustration of a zone of a sphere. A zone occurs when a sphere is cut by parallel planes that are…

Illustration of equal spheres with equilateral and equiangular triangles.

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

An illustration of a flanged spherical segment with a diameter of 10 inches. Illustration could be used…

An illustration showing how to construct a square circumscribed about a circle. "Draw the diameters…

An illustration showing how to construct a square inscribed in a circle. "Draw the diameter AB, and…

An illustration of a circle inscribed in a square. It can be used to show that the area of a circle…

The straight line is the simplest type of locus and the simplest first degree equation.

An illustration showing how to construct a talon, or two circle arcs that will tangent themselves, and…

An illustration showing how to construct a tangent between 2 given circles. "Join the centers C and…

An illustration showing how to construct a tangent to 2 given circles of different diameters. "Join…

An illustration showing how to construct a tangent circle to 2 given circles. "Join centers C and c…

An illustration showing how to construct a tangent to a circle through a given point in a circumference.…

An illustration showing how to construct a tangent to a circle through a given point outside of a circumference.…

An illustration showing how to construct a tangent circle to a circle with a given radius. "Through…

The exercise problem of creating a three piece elbow development or rolled out image of the cylinder…

A tire is ring shaped, the earliest tires were bands of iron placed on wooden wheels which were used…

An illustration showing a circle with radius r inscribed in a triangle with sides a, b, and c.

An illustration showing a circle with sectors D and E inscribed in a triangle with angles, A, B, and…

Illustration used to circumscribe a circle about a given triangle.

Illustration used to escribe a circle to a given triangle. "A circle which is tangent to one side of…