Weight of a Lineal Foot of Flat Bar Iron, in Lbs.

TRUTH is as impossible to be soiled by any outward touch as the sunbeam.-Lord Bacon.

Of all plane figures, the circle is the most capacious, or has the greatest area within the same limits. It is geometrically demonstrable that it has the same area as a right-angled triangle with a base equal to its circumference, and a perpendicular equal to its radius, that is, half the product of the radius and circumference. It is obviously larger than any figure, of however many sides, inscribed within its perimeter, and smaller than any circumscribed polygon. As a result of laborious calculations on this basis (pushed in one instance to 600 places of decimals without reaching the end), it has been ascertained that the ratio of the diameter to the circumference of any circle (sufficient) exact for all practical purposes), is as 1 : 3.1416 (3.141592653+) or in whole numbers, approximately, as 7: 22, or more nearly as 113:355. Hence, to find the circumference or diameter, the other quantity being known, multiply or divide by 3.1416; and to find the area, multiply half the diameter by half the circumference, or the square of the diameter by .7854 (3.1416÷4).

TO FIND THE SURFACE OF A GLOBE, multiply the square of the diameter by 3.1416.

TO FIND THE SOLIDITY OF A GLOBE, multiply the cube of th diameter by .5236.

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Table of Decimal Equivalents of 8ths, 16ths, 32nds

Handy Facts for Architects and Builders.

Pitch of tin, copper or tar-and-gravel roofs five-eighths of an inch to the foot and upwards.

The average weight of 20,000 men and women weighed at Boston was: Men, 1411⁄2 lbs.; women, 1241⁄2 lbs.

Smallest convenient size of slab for a 14-in. wash bowl, 21 by 24 in. Height of slab from floor, 2 ft. 6 in.

Urinals should be 2 ft. 2 in. between partitions; partitions 6 ft. high.

Space occupied by water-closets, 2 ft. 6 in. wide; 2 ft. deep. Dimensions of double bed, 6 ft. 6 in. by 4 ft. 6 in.

Dimensions of single bed (in dormitories), 2 ft 8 in. by 6 ft.

6 in.

Dimensions of a bureau, 3 ft. 2 in. wide, 1 ft. 6 in. deep, and upwards.

Dimensions of a common wash-stand, 2 ft. 4 in. wide, 1 ft. 6 in. deep.