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2. How many cords in a pile of wood 96 ft. long, 12 ft wide, and 8 ft. high? Ans. 72 cords. 3. A load of wood containing exactly 1 cord, is 5 ft. 4 in. wide, and 3 ft. 9 in. high; what is its length? Ans. 6 ft.

4. What is the height of a pile of wood containing 27 cords, if it is 75 ft. long and 10 ft. wide? Ans. 4.736 ft. 5. What will be the cost of the wood that can be piled in a shed 20 ft. long, 10 ft. wide, and 8 ft. high, at $4.75 a cord? Ans. $59.37.

BOARDS AND TIMBER.

359. Boards and Timber are usually estimated in what are called board feet, instead of in cubic feet.

360. A Board Foot is 1 foot long, 1 foot wide, and 1 inch thick. A cubic foot, therefore, contains 12 board feet. Hence, board feet may be reduced to cubic feet by dividing by 12, and cubic feet to board feet by multiplying by 12.

A standard board, in commerce, is 1 inch thick, and its contents in board feet are the product of its length and breadth in feet. Board feet are usually known as square feet. Boards are quoted by the hundred or the thousand, meaning a hundred square feet, or a thousand square feet. Round timber, as masts, etc., is estimated in cubic feet; hewn timber, as beams, etc., either in board or cubic feet; lumber and sawed timber, as planks, scantling, joists, etc., in board feet.

Rule I. To find the contents of a board, multiply the length in feet by the width in inches, and divide the product by 12.

Rule II. To find the contents of a plank, joist, etc., multiply the length in feet by the width and thickness in inches, and divide the product by 12.

NOTES.-1. If one of the dimensions is inches and the other two are feet, the product will be board feet.

2. When a board tapers regularly, the length must be multiplied by the mean width, which is half the sum of the two ends.

WRITTEN EXERCISES.

1. What are the contents of a board 14 feet long and 9 inches wide?

SOLUTION. Multiplying the length in feet by the width in inches, we have 14x9=126; and dividing by 12, we have 10 board feet, or #quare feet.

2. What are the contents of a board 16 feet long and 13 ft. wide? Ans. 24 sq. ft.

3. Required the contents of a board 20 ft. long, the ends being 18 and 14 inches respectively. Ans. 26 sq. ft. 4. How many square feet in 14 planks 16 ft. long, 18 inches wide, and 4 inches thick? Ans. 1344 sq. ft. 5. How many square feet in a stick of timber 40 feet long 14 inches wide, and 9 inches thick? Ans. 420 sq. ft.

6. What must be the width of a board 6 ft. 4 in. long that Ans. 18 inches.

it may contain 9 square feet?

7. How many square feet of inch boards will it require to make an enclosed box 3 ft. by 2 ft. 6 in. and 18 in. high on the outside, allowing for the overlapping of the boards? Ans. 293 sq. ft.

SUPPLEMENTARY PROBLEMS.

To be omitted unless otherwise directed.

8. What is the cost of 40 boards 12 ft. long, 15 in. wide, at $2.75 per hundred square feet?

Ans. $16.50.

9. What is the cost of 9 pieces of scantling 4 in. by 5 in. and 10 ft. long at $8.75 per thousand square feet? Ans. $1.81.

10. What is the cost of flooring a three-story house, the floors being 56 ft. by 32 ft. and the plank 1 inches thick, at $33 per thousand? Ans. $266.112.

11. I wish to fence a field 36 rd. long and 18 rd. wide, the posts to be set 9 ft. apart, the boards to be 18 ft. long, and 11 inches wide, the fence being 3 boards high; the posts cost $30 per C, and the boards $15.50 per M, and it required 2 men 3 days, at $3.50 each a day, to build the fence; required the number of posts, the amount of lumber, and the whole cost. Ans. 198 posts; 4900 sq. ft.; $156.357.

MASONRY, BRICKWORK, ETC.

361. Masonry is usually estimated by the perch and the cubic foot; sometimes by the square foot or the square yard.

362. A Perch of stone or of masonry is 16 ft. long. 1ft. wide, and 1 ft. high; it contains 24 cubic feet, but when stone is built into a wall, 22 cubic feet make a perch, 23 cu. ft. being allowed for mortar and filling.

363. Excavations and Embankments are estimated by the cubic yard. A cubic yard of earth is called a load.

364. Brickwork is generally estimated by the thousand bricks, but sometimes in cubic feet.

In estimating labor, bricklayers and masons measure the length of the wall on the outside. The corners are thus measured twice, but this is considered an allowance for the greater difficulty of building them No allowance is made for windows and doors, except by special con tract, in which case it is customary to allow one-half the space actually required. In estimating material, allowance is made for doors, windows and corners.

The average size of bricks is 8 in. x4x2, but Phila. and Baltimore bricks are 8 in. ×4×2; Maine bricks, 7 in. ×3×23; North River bricks, 8 in. ×3×2; and Milwaukee bricks, 8 in. ×4×23.

To build one square foot of wall 1 brick or 4 inches thick, requires 7 common bricks; 2 bricks, or 9 in. thick, 14 bricks; 3 bricks, or 13 in. thick, 21 bricks. In practice, the thickness of the wall is regarded as the same for each kind of brick.

Rule I.-To find the number of perches in a piece of masonry, divide the number of cubic feet by 244.

Rule II.-To find the number of common bricks required for a wall or building, multiply the number of square feet in the wall by 7, if the wall is 1 brick thick; by 14, if 2 bricks thick; by 21, if 3 bricks thick.

The following is a general rule for all kinds of brick:-To find the number of any kind of bricks required for a wall, or building, add

of an inch to the length and the thickness of the brick, divide 144 by the product of these two sums to find the number of bricks in a square foot of wall 1 brick thick, and multiply by the number of bricks in the thickness, and this product by the number of square feet in the wall.

NOTE.-An old rule was-Deduct of the solid contents for the mortar. and divide the remainder by the contents of one brick. We may also find the contents of a brick with the mortar surrounding it, and divide a cubic foot by this quantity, to find the number of bricks in a cubic foot.

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1. How many perches of masonry in a wall 60 ft. long, 4 ft. 6 in. high, and 15 inches thick?

SOLUTION. Multiplying the length, breadth, and height together, we have 60×4×14, or 337 cu. ft., which, divided by 244. the number of cubic feet in a perch, equals 13 perches.

2. What will be the cost of digging a cellar 42 ft. long, 28 ft. wide, and 6 ft. 6 in. deep, at $.42 a load, each load being a cubic yard? Ans. $118.904.

3. How many perches (244 cu. ft.) of stone, laid dry, will build a wall around a lot 20 rd. long and 18 rd. wide, the wall to be 5 ft. high and 2 ft. 6 in. thick? Ans. 6283 perches.

4. What will be the cost of filling in a street 600 feet long and 65 feet wide, averaging 4 ft. below grade, at $.52 a cubic yard? Ans. $3380.

5. How many bricks of average size will it require to build the walls of a house 48 ft. long, 25 ft. wide, and 21 ft. high, the wall being 13 in. thick (21 bricks to sq. ft.), allowing 240 sq.ft. for doors and windows? Ans. 57,435 bricks.

SUPPLEMENTARY PROBLEMS,

To be omitted unless otherwise directed.

6. Mr. Wilson had a well dug in his yard, 6 ft. in diameter and 15 ft. 9 in. deep; what did it cost at 50% a load? Ans. $8.25-. 7. What will be the cost of the bricks in a house 40 ft. square, 22 ft. high, the walls being three bricks thick, of Philadelphia brick, at $15 per M.? Ans. $1027.75.

8. What will be the cost of digging and walling the cellar of a house 45 ft. by 24 ft., the cellar being 6 ft. deep and the wall 7 ft. high and 14 ft. thick, if the excavating cost 45 a load, and the masonry $4.25 a perch? Ans. $374.59.

MEASURES OF CAPACITY.

365. Measures of Capacity are volumes used to determine the quantity of fluids and many dry substances.

366. The Principal Measures of capacity are the gal lon for liquid substances, and the bushel for dry substances.

CAPACITY OF CISTERNS, ETC.

367. The Capacity of Cisterns, etc., is usually expressed in gallons or barrels.

368. The Standard Liquid Gallon of the United States contains 231 cubic inches, and is equal to about 8 lb. Avoirdupois of pure water.

369. The Barrel of 31 gallons, and the hogshead of

63 gallons, are used in measuring the capacity of cisterns, vats, tanks, etc. When used as the names of vessels, tuese terms express no definite quantity.

The Imperial Gallon of Great Britain contains 277.274 cubic inches, and is equal to about 1.2 U. S. gallons. The beer gallon contains 282 cubic inches, but is now seldom used. A cubic foot of pure water weighs 1000 oz. Avoirdupois.

Rule I.—To find the capacity of a cistern or vessel in gallons, divide the contents in cubic inches by 231.

Rule II. To find the cubic inches in a given number of gallons, multiply the given number of gallons by 231.

WRITTEN EXERCISES.

1. How many gallons of water will a tank 6 ft. long, 4 ft. wide, and 2 ft. 3 in. deep, contain?

SOLUTION.-The contents of the tank equal 6×4×2, which are 54 cubic feet; multiplying by 1728 to reduce to cubic inches, we have 93312 cu. in.; dividing by 231, the number of cubic inches in a gallon, we have 4034 gallons.

2. How many gallons of water are contained in a tank 15 ft. long, 3 ft. wide, and 3 ft. 6 in. deep? Ans. 1178 gallons. 3. How many Imperial gallons would be contained in the same tank? Ans. 981.55+ Imp. gal. 4. How many cubic feet in a cistern containing 45 hogsheads? Ans. 3788 cu. ft. 5. A cistern 8 ft. square contains 54 hhd.; what is its depth? Ans. 7.11- ft.

6. How many barrels of water can be contained in a tank measuring 7 ft. square by 4 ft. deep? Ans. 46 barrels. 7. How many hogsheads of water can be contained in a well whose diameter within the curb is 4 ft., and depth 12 feet? Ans. 22.66+ hhd.

SUPPLEMENTARY PROBLEMS,
To be omitted unless otherwise directed.

8. The diameter of a well is 3.5 ft., and it contains 16 hhd. of

water; what is the depth of the water?

9. A tank 4 yd. long, 2 yd. wide, and 6 ft.

of water; what is the weight of the water?

Ans. 14.44+ ft. deep, is half full

Ans. 13,500 lb.

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