Book three (1901)

For Reference

Cone. A cone may be regarded as a pyramid whose base contains an infinitely large number of sides, so as to become a circle.

Cylinder. A cylinder is a solid whose ends or bases are circles. Diagonal. A diagonal is a straight line connecting two angles that are not adjacent to each other.

Diameter.

the center.

The diameter is the distance across the circle through

Equilateral triangle. An equilateral triangle is a triangle all of whose sides are equal.

Falling bodies. A heavy body will fall about 16 feet in one second, 2 × 2 × 16 feet in two seconds, 3 × 3 × 16 feet in three seconds, etc. The distance through which a body falls is proportional to the square of the number representing the time of the fall.

Foot-pound. A foot-pound is the amount of work expended in raising one pound one foot high.

Forces. When two or more forces act upon an object at the same time, the effect is the same as if each force acted alone.

Gallons. A gallon contains 231 cu. in. A gallon of water weighs about 83 lb. A cubic foot of water weighs 621 lb.

Hexagon. A hexagon is a polygon having six sides.

Horse power.

A horse power is sufficient power to raise 550 pounds one foot per second.

Isosceles triangle. An isosceles triangle is a triangle two of whose sides are equal.

Lateral surface. The lateral surface of a solid is the surface of its sides exclusive of its ends or bases.

The lateral surface of a cylinder is equal to the circumference of its base multiplied by its altitude.

The lateral surface of a regular pyramid or cone is equal to one half of the product of the perimeter or circumference of the base and the slant height.

Laths. A lath is 4 ft. long and 11⁄2 in. wide. Laths are usually left of an inch apart when nailed. There are 50 laths in a bunch. A bunch will cover 3 square yards of surface.

Lever. In any application of the lever the number of units of the power times the number of units of its distance from the fulcrum is

For Reference

equal to the number of units of the weight times the number of units of its distance from the fulcrum.

Light. Light travels at the rate of about 186,000 miles a second. Momentum. The momentum of a body is its weight in pounds multiplied by the number of feet through which it is moving per second.

Oblong. An oblong is a rectangle whose length exceeds its width. Obtuse angle. An obtuse angle is larger than a right angle. Paper. In America wall paper is usually 18 in. wide. A single roll is 24 ft. long, a double roll 48 ft. long.

Parallelogram. A parallelogram is a quadrilateral whose opposite sides are parallel to each other.

Pentagon. A pentagon is a polygon having five sides.

Perimeter. The perimeter of a plane figure is its boundary line. Plane. A plane is a surface such that a straight line joining any two points in it lies wholly within that surface.

Polygon. A polygon is a plane figure bounded by straight lines. In a regular polygon the sides are all equal and the angles are all equal.

Pressure. The pressure of liquids at any point is equal in all directions.

Prism.

A prism is a solid whose ends are polygons and whose sides are parallelograms.

Pyramid. A pyramid is a solid whose base is a polygon and whose lateral faces are triangles.

Quadrilateral. A quadrilateral is a polygon having four sides.

Radius. The radius is the distance from the center of a circle to the circumference.

Rectangle. A rectangle is a quadrilateral all of whose angles are right angles.

Right angle. A right angle is an angle of 90°.

Right triangle. A right triangle is a triangle which has one right angle.

Four

Shingles. Shingles are packed and bound in bunches. bunches of shingles make 1000. A thousand shingles will cover 100 square feet, when laid with 4 inches exposed to the weather.

For Reference

Slant height. The slant height of a pyramid is the perpendicular distance from its vertex to one of the sides of its base.

Sound. Sound travels in the air at the rate of about 1100 feet a second, and in the water at the rate of about 4700 feet a second.

Specific gravity. The specific gravity of a substance is the ratio of its weight to the weight of water.

Sphere. A sphere is a solid, all points of whose surface are equally distant from the center.

Square. A square is a quadrilateral, all of whose angles are right angles and all of whose sides are equal.

Stone masonry.

Stone is reckoned in cubic feet, in cords, or in

perches. A perch is 24 cu. ft.

Surface. The surface of a sphere is equal to the product of its diameter and its circumference.

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