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Cubic Measure.

Table.
1728 Cubic Inches (cu. in.) - 1 Cubic Foot (cu. ft.).
27 Cubic Feet

1 Cubic Yard (cu. yd.).
16 Cubic Feet

= 1 Cord Foot (cd. ft.). 8 Cord Feet, or

1 Cord of Wood (ed.). 128 Cubic Feet $

Scale : 1728, 16, 8, and 1728, 27.

EXERCISES. Reduce :

1. 15 cu. yd. 18 cu. ft. 16 cu. in. to cu. inches. 2. 730,960 cu. in. to cu. yd., etc. 3. 32 cu. ft. 114 cu. in. to cu. inches. 4. 174,964 cd. ft. to cords. 5. 7680 cu. ft. to cords. 6. 2160 cu. ft. to cu. yd. 7. 62,950 cu. in. to cu. ft. 8. 3 cd. ft. 8 cu. ft. to cu. ft. 9. 78,976 cd. ft. to cords. 10. 8797 cu. ft. to cords. 11. 466 cd. 124 cu. ft. to cu. ft. 12. 1216 cu. ft. to cords. 13. 19,528 cd. ft. to cords. 14. 988 cu. ft. to cu. yd. 15. cd. to units of lower denominations.

FORMULÆ.

length x breadth x height (thickness).

1. Volume

Height 2.

Thickness 3. Breadth 4. Length

} = volume +- length x breadth.

= volume = length x height.
= volume breadth x height.

UNITS.

The cubic foot for bricklaying, masonry, and hewn timber.
The cubic yard for embankments, excavations, and masonry.
A cubic yard of common earth is sometimes called a load.

The perch of stone, 161 ft. long, 11 ft. wide, and 1 ft. high, equal to 24 cu. ft. It is customary, however, to call 25 cu. ft. a perch.

Brick.—The size of a common brick is 8 X 4 X 2 in., and for ordinary calculation it is sufficiently accurate to reckon 27 bricks to the cubic fuot, laid dry, or 22į laid in mortar.

Brickwork is generally estimated by the thousand bricks. In estimating material, allowance is made for openings in walls, as doors, windows, etc.

In estimating labor, the length of each wall is measured on the outside, and thus each corner is measured twice

Sometimes, by special contract, an allowance is made for one-half the openings and corners.

A pile of wood 8 ft. long, 4 ft. wide, and 4 ft. high is a cord.

A cord foot is one foot in length of such a pile; that is, 1 ft. long,

4 ft. wide, and 4 ft. high. 1 2 3 4

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PROBLEMS.

1. Find the volume of:

1. A block of marble 9 ft. long, 5 ft. wide, 31 ft.

thick. 2. A cube whose edge measures 2 ft. 9 in. 3. A pile of wood 36 ft. long, 6 ft. high, 4 ft. wide. Suggestion: 36 X X 4 Cancel.

6 . 4. The contents of a box measuring 18 in. by 16 in.

by 14 in. 5. A cube 1 in. long, 1 in. wide, 1 in. high. 6. The earth in a cellar 36 ft. X 24 ft. x 52 ft. 7. Excavation for a reservoir 80 ft. by 60 ft. by 10 ft.

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8. Excavation for a cistern measuring 15 ft. by 14

ft. by 13 ft.
9. A cube whose sides are each 6 in. square.

10. A brick measuring 8 X 4 X 2 in.
2. Why are there 16 cu. ft. in a cord-foot of wood ?

3. Find the perches of masonry in a wall 38 ft. by 4 ft. by 1] ft.

38 X 4 X 11 Suggestion :

Cancel.

24
4. Reduce 16 p. 141 cu. ft. to cu. ft.

5. A cube whose edge is 9 yds. equals in volume how many cubes whose edge is one foot ?

6. How many blocks of one cubic inch can be sawed from a cube of 7 ft., if there is no waste in sawing?

7. How many cords in a pile of wood measuring 72 ft. by 13 ft. by 9 ft. ?

8. Find the cost of digging a cellar 50 ft. long, 40 ft. wide, 51 ft. deep, at $11 per cubic yard ?

9. How many cubic feet in two-thirds of a cubic yard ? 10. How many cd. ft. in 5 cords of wood ?

11. How many cu. yd. of air in a room 24 ft. by 18 ft. by 12 ft.?

12. Find the number of loads of ashes in a rectangular pit measuring 12 ft. by 4 ft. by 2 ft. 6 in. ?

13. Find the cost of building a stone wall 55 rds. long, 41 ft. high, and 1 yd. thick, at $7.25 a perch?

14. How many bricks would make the bulk of 9 loads ?

15. How many perches of masonry in a wall 6 ft. high, 2 ft. thick, inclosing a plot of ground 40 rds. square ?

16. How many bricks, laid in mortar, will build a house 57 ft. long, 45 ft. wide, and 30 ft. high, the wall to be 1} ft. thick ; deducting for 15 windows, 8} by 31 ft., and 8 doors, 73 by 37 ft. wide ?

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17. What will it cost to dig a cellar 35 ft. long, 22 ft. wide, and 6 ft. deep, at $.25 for the removal of a cubic foot of earth ?

18. A pile of wood containing 197 cd. is 66 ft. long and 6 ft. wide. Find its height?

19. Prescribing 18 in. for the height and 6 ft. for the length of a wagon body, how wide must it be made to hold a load ?

20. Find the length of a wall, 1 ft. thick and 4 ft. high, that 1000 bricks, laid in mortar, will build.

21. A river 30 ft. deep and 20 yd. wide flows 4 mi. an hour. How many cu. ft. of water pass a given point in a minute?

Board Measure. 1. Boards whose thickness is one inch or less are measured by the square foot. A board 12 ft. long, 1 ft. wide, 1 in. thick

sq.

ft. board measure. 2. All hewn or squared lumber is estimated and sold by board measure, thickness beyond one inch becoming a factor.

= 12

EXERCISE. How many feet, board measure, are there in a timber 40 ft. long, 9 in. wide, and 6 in. thick ?

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Explanation. 9 in. l'a ft. Since 410 X 12

the number of board feet when the thickness is one inch, 6 times that, or 40 Xiu Xi = the number of board feet when the thickness is 6 in. By cancelling we have 180 ft.

FORMULA. Number of feet board measure = length (feet) x width (feet) x thickness (inches).

NOTE.—When the board tapers uniformly, use the mean width, i.e., half the sum of the two end widths.

PROBLEMS.

1. Find the number of board feet in the following pieces of lumber :

1. 16 ft. by 9 in. 6. 15 ft. by 18 in. by 4 in.
2. 15 ft. by 10 in. 7. 35 ft. by 15 in. by 12 in.
3. 12 ft. by 11 in. 8. 12 ft. by 5 in. by 4 in.
4. 11 ft. by 12 in. 9. 40 ft. by 9 in. by 6 in.

5. 14 ft. by 16 in. 10. 16 ft. by 8 in. by 1 in. 2. Find the number of feet in a joist 20 ft. long, 8 in. wide, and 4 in. thick.

3. A man has 70 planks measuring 16 ft. by 8 in. and 1} in, thick. How many feet, board measure, has he?

4. Find the width of a 2-in. plank 16 ft. long that contains 50 ft.,

board measure. 5. Find the contents of a board 18 ft. long, 1 ft. 8 in. wide at one end and 14 in. at the other.

6. Find the cost of 38 boards 16 ft. long, 12in. wide, at $24 per C. 7. Find the cost of the following, at $20 per M.:

160 boards 16 ft. by 11 in.
170 boards 15 ft. by 10 in.
70 plank 14 ft. by 10 X 3 in.
70 scantling 12 ft. by 4 X 2 in.

50 rafters 25 ft. by 5 X 3 in. 8. How many feet, board measure, are there in a plank 17 ft. long, 22 in. wide at one end, 13 in. wide at the other, and 3 in. thick ?

9. Find the cost of 72 boards, each 11 ft. long, 16 in. wide, and jin, thick, at $16.50

$16.50 per M. 10. In a tapering board, 11 ft. long, 18 in. wide at one end, 11 inches wide at the other, and 3 in. thick, how many feet?

11. A room is 20 by 25 ft. What will be the cost of floor

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