SECTION LXX.

MEASUREMENTS OF GRAIN AND HAY.

746. Grain is usually estimated in this country by the bushel or by the cental. (Art. 332.)

747. The Standard Bushel in the United States contains 2150.4 cubic inches. Hence, a cubic foot is nearly .8 of a bushel. 748. Hay is usually bought and sold by the ton.

About 550 cubic feet of clover, or 450 feet of meadow-hay, well settled, as an average, in large mows, make a ton.

749. Rules for Estimating Grain.-1. To find the quantity, in bushels, of grain in a bin or wagon, multiply the contents in cubic feet by .8.

2. To find the quantity, in bushels, of grain when heaped upon a floor, make the heap in the form of a cone, and multiply the area of the base by one-third of the altitude, and the result by .8.

If the grain be heaped against the side of a wall in the form of a half cone, take half the result by Rule 2, or, if heaped against an inner corner, take one fourth.

750. Rule for Estimating Hay.-1. To find the quantity, in tons, of hay, in mows, well settled, divide the contents by 550 for clover, or by 450 for meadow-hay.

PROBLEMS.

1. How many bushels of wheat will a bin hold that is 6 feet long, 4 feet wide and 5 feet deep?

Ans. 96.

2. A wagon 9 feet long, 3 feet wide and 3 feet deep is two thirds full of shelled corn. How many bushels does it

contain?

3. A farmer had a heap of oats, which when made in a conical form, measured in the circumference of the base 22

feet, and in altitude 6 feet. How many bushels does it conAns. 61.6.

tain ?

4. In the inner corner of a building corn is heaped in the form of a quarter cone, whose altitude is 6 feet and slant height 10 feet. What is the quantity of corn?

Ans. 80 bushels. 5. A heap of grain, piled against a wall, measures a height of 9 feet and a semi-circumference of 33 feet. How many bushels does it contain? Ans. 415.8.

6. A bin 6 feet long, 4 feet wide and 5 feet deep is filled with rye. What is its value at $2 per cental?

Ans. $107.52.

7. How many tons of meadow-hay in a portion of a stack, dry and settled, which is 10 feet long, 9 feet wide and 6 feet high?

8. What is the value, at $30 a ton, of a mow of cloverhay that is 24 feet long, 12 feet wide and 9 feet high?

SECTION LXXI.

GAUGING.

751. Gauging is the process of finding the capacity of casks and other vessels.

752. The Mean Diameter of a cask is the diameter of an equivalent cylinder having the same length as the cask.

It is nearly equal to the head diameter plus two thirds of the difference between that and the long diameter, or three fifths when the staves are but slightly curved.

753. The Ullage, or wantage, of a cask is the quantity it lacks of being full.

754. Rules for Gauging.—1. Multiply the product of the square of the mean diameter and the length or depth of the cask, expressed in inches, by .0034, and the result will be its capacity in gallons.

2. Multiply the square of one third of the sum of the head, mean and bung diameters, expressed in inches, by the height of the liquid in inches, and that product by .0034, and the result will be the contents of an ullage cask.

PROBLEMS.

1. How many gallons is the capacity of a cask whose length is 40 inches and mean diameter 25 inches? Ans. 85 gallons. 2. Required the quantity of vinegar in a cask whose bung and head diameters are 37 and 28 inches, and the height of the liquid 10 inches. Ans. 37.026 gallons.

3. How much will a cask of molasses cost whose mean diameter is 30 inches and length 36 inches, at $.55 per gallon? Ans. $60.58.

TEST QUESTIONS.

755.-1. What are the dimensions of a BOARD FOOT? How many board feet are one cubic foot?

2. What kind of timber is LUMBER? In what is squared or hewn timber estimated? What are the rules for finding the contents of lumber and squared timber?

3. In what is ROUND TIMBER estimated? What is the mean girt of a tapering log? What is the mean breadth and thickness of tapering squared timber? What is the rule for finding the cubic contents of round timber?

4. By what is STONE MASONRY estimated? What is a perch of stonework? What is the rule for finding the number of perches of stone-work? 5. How is BRICKLAYING usually estimated? What is the rule for finding the number of bricks in brick-work?

6. How is GRAIN usually estimated? How much does the standard bushel contain? What is the rule for finding the quantity, in bushels, of grain in a bin or wagon? For finding the quantity of grain when heaped upon a floor?

7. How is hay bought and sold? About how many cubic feet of clover make a ton? About how many cubic feet of meadow-hay make a ton? What is the rule for finding the quantity of hay in tons?

8. What is GAUGING? What are the rules for gauging?

SECTION LXXII.

METRIC SYSTEM.

756. The Metrie System is a system of weights and measures based upon a unit called a meter.

757. The Meter is one ten-millionth part of the distance from the equator to either pole, measured on the earth's surface at the level of the sea.

758. The Names of derived metric denominations are formed by prefixing to the name of the primary unit of a meas

ure

Milli (mill'e), a thousandth; Centi (sent'e), a hundredth; Deci (des'e), a tenth;

Deka (dek'a), ten; Hecto (hek'to), one hundred; Kilo (kil'o), a thousand; Myria (mir'ea), ten thousand.

This system, first adopted by France, has been extensively adopted by other countries, and is much used in the sciences and the arts. It was legalized in 1866 by Congress to be used in the United States, and is already employed by the Coast Survey, and to some extent by the Mint and the General Post-Office.

The illustration adjoining shows the length of 10 centimeters, or a tenth of a meter, compared with 4 inches, or a third of a foot.

The nickel 5-cent pieces are each two hundredths of a meter in diameter; hence, 50 of

2

3

them placed side by side in a straight line will measure 1 meter.

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The simplicity and utility of the system, recognized now by all civilized nations, is likely to lead to its general adoption, and to the great advantage of home and foreign trade.

In the tables the units most used are denoted by CAPITALS or by plain Roman type.

LINEAR MEASURES.

759. The Meter is the primary unit of lengths.

The Meter is used in ordinary measurements; the Centimeter, or Millimeter, in reckoning very small distances; and the Kilometer, for roads or great distances.

A Centimeter is about of an inch; a Meter is about 3 feet 3 inches and of an inch; a Kilometer is about 200 rods, or § of a mile.

SURFACE MEASURES.

760. The Square Meter is the primary unit of ordinary surfaces; and,

761. The Are (air), a square each of whose sides is ten meters, is the unit of land measures.

TABLE.

100 sq. millimeters (sq. mm.) are 1 sq. centimeter (sq. cm.)

A Square Meter, or 1 Centiare, is about 10 square feet, or 1 square yards, and a Hectare is about 2 acres.

CUBIC MEASURES.

762. The Cubic Meter, or Stere (stair), is the primary unit of a volume.

TABLE.

1000 cu. millimeters (cu. mm.) are cu. centimeter (cu. cm.)