"A complex crystal of apatite with the faces of a third-order pyramid upon it." — Ford, 1912

Apatite

"A complex crystal of apatite with the faces of a third-order pyramid upon it." — Ford, 1912

"Base Ball is a field game played principally in the United States. It originated in the English school-boy game of "rounders;" but it has been so improved and so generally played as to merit its name of "the National game of America." The plaing of baseball has become largely a business or a "profession," and skilled players receive large salaries. As an amateur game, however, it is also most popular."—(Charles Leonard-Stuart, 1911)

Baseball Diamond

"Base Ball is a field game played principally in the United States. It originated in the English school-boy…

Illustration of a circle divided into thirds. One third is shaded.

1/3 Circle

Illustration of a circle divided into thirds. One third is shaded.

Thomas Jefferson (April 13, 1743 – July 4, 1826) was the third President of the United States (1801–1809), the principal author of the Declaration of Independence (1776), and one of the most influential Founding Fathers for his promotion of the ideals of republicanism in the United States. Major events during his presidency include the Louisiana Purchase (1803) and the Lewis and Clark Expedition (1804–1806).

Thomas Jefferson

Thomas Jefferson (April 13, 1743 – July 4, 1826) was the third President of the United States (1801–1809),…

"In the third order of lever the power acts between the prop and the resistance, where also P : W :: BF : AF, and the pressure on the fulcrum is P-W, or the power less the weight."——Pettigrew, 1874

Third Kind of Lever

"In the third order of lever the power acts between the prop and the resistance, where also P : W ::…

The heraldic charge borne by the third eldest son in a family.

The Mullet

The heraldic charge borne by the third eldest son in a family.

A circle divided into thirds.

Fraction Pie Divided into Thirds

A circle divided into thirds.

A circle divided into thirds with one third separated.

Fraction Pie Divided into Thirds

A circle divided into thirds with one third separated.

One third of a circle.

One Third of a Fraction Pie

One third of a circle.

One third of a circle.

One Third of a Fraction Pie

One third of a circle.

One third of a circle.

One Third of a Fraction Pie

One third of a circle.

Two thirds of a circle.

Two Thirds of a Fraction Pie

Two thirds of a circle.

Two thirds of a circle.

Two Thirds of a Fraction Pie

Two thirds of a circle.

Two thirds of a circle.

Two Thirds of a Fraction Pie

Two thirds of a circle.

A circle subdivided into two thirds and two sixths.

Two Thirds and Two Sixths of a Pie Fraction

A circle subdivided into two thirds and two sixths.

Illustration of a square divided into thirds. One third is shaded.

1/3 Square

Illustration of a square divided into thirds. One third is shaded.

A lever of the third class

Third Class Lever

A lever of the third class

"A lever is an inflexible bar freely movable about a fixed axis called the fulcrum. If the power is between the weight and the fulcrum the lever is of the third class." — Avery, 1895

Third class lever

"A lever is an inflexible bar freely movable about a fixed axis called the fulcrum. If the power is…

"In the third and last kind of lever, the weight is placed at one end, the fulcrum at the other end and the power between them, or the hand s between the fulcrum and the weight." -Comstock 1850

Third-class Lever

"In the third and last kind of lever, the weight is placed at one end, the fulcrum at the other end…

"Third class lever." -Comstock 1850

Third Class Lever

"Third class lever." -Comstock 1850

"A Lever of the Third Kind is one in which the power is between the weight and the fulcrum." —Quackenbos 1859

Third Class Lever

"A Lever of the Third Kind is one in which the power is between the weight and the fulcrum." —Quackenbos…

Illustration showing three triangles. This is used to show the following theorem: If two triangles have two sides of the one equal, respectively, to two sides of the other, but the included angle of the first triangle greater than the included angle of the second, then the third side of the first is greater than the third side of the second.

Three Triangles Used to Compare Sides

Illustration showing three triangles. This is used to show the following theorem: If two triangles have…

Illustration showing that one foot is one third of a yard.

Yard And Foot

Illustration showing that one foot is one third of a yard.