A sphere with arcs and poles. "The distance of all points in the circumference of a circle of a sphere…
A sphere with quadrants and poles. "A point on the surface of a sphere, which is at the distance of…
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 two intersecting spheres. "The intersection of two spherical surfaces is the circumference…
Illustration of a sphere with a polyhedral angle whose vertex is at the center of the sphere and whose…
Illustration of equal spheres with equilateral and equiangular triangles.
Illustration of half of an ellipse. "If d denotes the abscissa of a point of an ellipse, r and r' its…
Illustration of half of an ellipse. "The ordinates of two corresponding points in an ellipse and its…
Illustration of half of an ellipse and its auxiliary circle used to construct an ellipse by points,…
Illustration of half of an ellipse. The square of the ordinate of a point in an ellipse is to the product…
Illustration of half of an ellipse. "The sum of the distances of any point from the foci of an ellipse…
Illustration of half of an ellipse. "If through a point P of an ellipse a line is drawn bisecting the…
Illustration of how to draw a tangent to an ellipse from an external point.
Illustration showing the tangents drawn at two corresponding points of an ellipse and its auxiliary…
Illustration showing that tangents drawn at the ends of any diameter are parallel to each other.
Illustration showing that if one diameter is conjugate to a second, the second is conjugate to the first.
Illustration of a hyperbola and its auxiliary circle. "Any ordinate of a hyperbola is to the tangent…
Illustration of a circle with a sector. "A sector of a circle is the space included between an arc and…
Illustration of intersecting circles. "If two circles intersect each other, the line joining their centers…
Illustration of tangent circles. One circle is said to be tangent to another circle when they touch…
"If from any point on the circumference of a circle, a perpendicular be let fall upon a given diameter,…
"If AOB is an angle of 1 ° on the larger circle, it is also 1 ° on the smaller concentric circle,…
"In trigonometry, the arcs of circles are used to measure angles. All angles are supposed to have their…
Bones of the arm and hand. Labels: a, large end of ulna; b, radius; c, small end of the ulna; d, carpal…
Right triangle OCA, inside of Circle O is used to show that side AC is "opposite" O and side OC is "adjacent"…
The coversedsine is equal to 1 minus the sine. In this figure, AE is parallel to OB; hence, EO = AC…
Double Eagle ($20.00) United States coin from 1849. Obverse has a left-facing image of Liberty wearing…
Dollar ($1.00) Obverse sun over dial surrounded by the inscription - CONTINENTAL CURRENCY 1776. Reverse…
Half Cent (1/2 cent) United States coin from 1809. Obverse has a left-facing profile of Liberty surrounded…
Illustration of the method of finding the projection, in the form of an ellipse, of the top of a cylinder…
Illustration showing an ellipse (and circle) as a section from a cylinder.