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

Diagram used to prove the theorem: "A spherical angle is measured by the arc of a great circle described…

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

Diagram used to prove the theorem: "The volume of a spherical segment is equal to the sum of two cylinders…

Diagram used to prove the theorem: "In a spherical triangle, the greater side is opposite the greater…

Diagram showing 2 superimposed symmetrical spherical triangles.

"An instrument for measuring the radii of spheres; a sphere-measurer. It is of especial service to opticians…

Diagram showing a spherical triangle constructed by the intersection of polar arcs.

Diagram showing a spherical triangle constructed by the intersection of polar arcs.

Diagram showing a spherical triangle constructed by the intersection of polar arcs.