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2. What are the contents of a board 16 feet long and li 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. Wbat must be the width of a board 6 ft. 4 in. long that it may contain 9. square feet?

Ans. 18 inches. 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. 29 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. $1.311 10. What is the cost of flooring a three-story house, the foors being 56 ft. by 32 ft. and the plank 14 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 lum. ber, and the whole cost. Ans. 198 posts; 49001 sq. ft.; $156.357.

MASONRY, BRICKWORK, ETC. 361. Masonry is usually estimated by the perch and tbe cubic foot; sometimes by the square foot or the square yard.

362. A Perch of stone or of masonry is 161 ft. long, 1}ft. wide, and 1 ft. high ; it contains 24 cubic feet, but when stone is built into a wall, 22 cubic feet make a perch, 24 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 contract, 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.X 4X2, but Phila. and Baltimore bricks are 84 in. X 44 X2}; Maine bricks, 7} in. X33X28; North River bricks, 8 in.X31X24; and Milwaukee bricks, 84 in. x 47 x 25.

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 1.—To find the number of perches in a piece of masonry, divide the number of cubic feet by 241.

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 to 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 190t by this quantity, to find the number of bricks in a cubic foot.

WRITTEN EXERCISES.

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 bave 60 x 41 x1, or 3371 cu. ft., which, divided by 248, the number of cubic feet in a perch, equals 1371 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. $118.903. 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 6 ft. high and 2 ft. 6 in. thick ?

Ans. 628%; perches. 4. What will be the cost of filling in a street 600 feet long and 65 feet wide, averaging 41 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 7ft. high and 1} ft. thick, if the excavating cost 45% a load, and the masonry $4.25 a perch?

Ans. $374.5911

MEASURES OF CAPACITY.

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

366. The Principal Measures of capacity are the gallon 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 8j 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 6X 4X24, 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 4037gallons.

2. How many gallons of water are contained in a tank 15 ft. long, 3 ft. wide, and 3 ft. 6 in. deep? Ans. 117811 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 hogsbeads ?

Ans. 37804 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 41 ft., and depth 12 get?

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 164 hlid. of water; what is the depth of the water ?

Ans. 14.44 + ft. 9. A tank 4 yd. long, 2 yd, wide, and 6 ft. deep, is half full of water; what is the weight of the water? Ans. 13,500 lb.

10. A tank 7 ft. long, 5 ft. wide, and 3 11. deor, can be emptied by a waste pipe in 2 hours; how many gallons are discharged in 1 minute?

Ans. 64 gallons. 11. Mr. Cornwell constructed a tank in bis attic 8 ft. 6 in, long, 4 ft. 3 in, wide, and 2 ft. 6 in. deep; how many hogsheads of water will it hold, and what will be the weight ?

Ans. 10.72 + hhd.;

564437 lb. 12. A reservoir 32 ft. long, 27 ft. wide, and 10) ft. deep, is full when it becomes necessary to draw off the water to clean it out; what will be the expense of pumping the water ont at 10 cents a hogshead ?

Ans $76.94+.

measure.

CAPACITY OF BINS, ETC. 370. The Capacity of Bins, etc., is usually expressed in bushels.

371. The Standard Bushel of the United States is a cylindrical measure 18} in. in diameter and 8 in. deep, containing 2150.42 cubic inches. The Bushel.-Grain, seeds, and small fruits are sold by stricken

Potatoes, corn in the ear, large fruits, coal and other bulky articles are sold by heaped measure.

In practice we may call 5 stricken bushels equal to 4 heaped bushels.

Coal.-Coal is bought and sold in large quantities by the ton; in small quantities by the bushel, 28 heaped bushels, or about 43.5 cu. ft. being considered equal to a ton.

Ordinary anthracite coal measures from 36 to 40 cu. ft. to the ton; bituminous coal, from 36 to 45 cu. ft. to the ton. Lehigh white ash coal, egg size, measures about 34} cu. ft. to the ton; Schuylkill white ash 35 cu. ft., and pink, gray, or red ash, 36 cu. ft. to the ton.

Hay.--Hay, when loose or in loads, or upon a scaffold, measures iboui 500 cu. ft. to the ton; on a mow, 400 cu. ft.; and in large well-settled stacks, 10 cu. yd.

Rule I.-To find the capacity of a bin in bushels, divide the contents in cubic inches by 2150.42.

Rule II.—To find the cubic feet in a given number of bushels, multiply the number of bushels by 2150.42, and divide by 1728.

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