Circle
a plane figure contained by one line, which is called the circumference, and is such that all straight lines drawn from a certain point (the center) within the figure to the circumference are equal to one another. The properties of the circle are investigated in books on geometry and trigonometry.
Properly the curve belongs to the class second order. A great circle of a sphere is one that has its center coinciding with that of the sphere. The celebrated problem of "squaring the circle" is to find a square whose area shall be equal to the area of any given circle. It is not possible to do so.
All that can be done is to express approximately the ratio of the length of the circumference of the area of the figure from this approximation. If the diameter be called unity, the length of the circumference of the circle circle is found by multiplying this number by the square of the radius. Thus the area of a circle of 2 feet radius is proximately. For trigonometrical calculations the circumference of the circle is divided into 360 equal parts called degrees, each degree is divided into 60 minis divided into 360 equal parts called degrees, each degree is divided into 60 minutes, and each minute into 60 seconds. river, the Ohio and Erie canal, and the Cincinnati and Muskingum Valley and the Norfolk and Western railroads, 28 miles S. of Columbus. It derives its name from a circular earth work built ous churches, a high school, graded pubworks, canneries, and flour mills, numerlic schools, several daily and weekly States Supreme Court. In 1920 there newspapers, 3 National banks, etc. Pop. court in the