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= 1 fathom.
= 1 cable length.
x REM.—1 nautical league 3 equatorial miles = 3.45771 statute miles. 60 equatorial miles = 69.1542 statute miles = 1 equatorial degree (°). 360° = the circumference of a circle. 360 equatorial degrees = the circumference of the earth,
= 1 link (.). 25 links
= 1 pole (p.). 100 links, 4 poles, 66 feet = 1 chain (ch.). 10 chains
= 1 furlong. 8 furlongs, or 80 chains = 1 mile.
= 1 rood. 4 roods = 1 acre. 640 acres = 1 square mile,
mile, termed a Section.
A Square is a surface bounded by four equal sides, its angles are also equal; thus,
This figure, ABCD, repre1/1213141171181111 4 ।।
sents a square foot, considerVIII
ing each of the small spaces 41 III
as an inch. The sides, AB, :11
BC, AD, and DC, each equal 21
to 12 inches in length. The ||||
angles, A, B, C, and D, are 111
equal; that is, if one is placed II 4/11091812161714? ATT on the other, the sides respec
tively will coincide. AB is 12 inches long, and every inch in width makes 12 square inches ; and the 12 inches in width, which is either AD or BC, makes 12 x 12 = 144 sq. in.; hence the correspondence of linear and square measure; thus,
LINEAR MEASURE. 12 inches = 1 foot. 3 feet = 1 yard. 54 yards = 1 rod, pole, or perch.
SQUARE MEASURE. 12
square inches = 1 square foot. 3 x 3 = 9
feet = 1 square yard. 51 x 54 = 304 square yards = 1 square rod; 51
also called perch.
CUBIC MEASURE. x 12 x 12 x 12 = 1728 cubic inches = 1 cubic foot.
3 x 3 x 3 = 27 cubic feet = 1 cubic yard.
A Cube is a solid figure bounded by six equal squares; the square on page 72 represents the base or any other side, as the sides are all equal; the length of all the edges are equal, and the angles are all equal. If the above figure have 12 inches altitude added to it, every inch will make 144 cubic inches and 12 inches in altitude, 144 x 12 = 1728, which is the number of cubic inches in a cubic foot.
40 cubic feet of round timber, or 50 cubic feet of hewn timber = 1 Ton.
A perch of stone is 160 feet long, 11 feet wide, and 1 ft. high = 244 solid feet.
This measure is used for all liquids.
4 quarts = 1 gallon (gal.).
Chaldean In all liquids, except ale, beer, and milk, the gallon is 231 cubic inches.
In ale, beer, and milk, it is 282 cubic inches.
REM.- In the former 317 gallons is called a barrel, 63 gallons a hogshead, 42 gallons a tierce, 84 gallons a puncheon, and 126 gallons a pipe, and 2 pipes a tun. In the latter, 36 gallons barrel, and 54 gallons = a hogshead ; these, however, are not measures, but only vessels.
is used for grain, fruits, vegetables, coal, salt, etc.
The wine gallon of United States
cu. in. The beer gallon of United States
cu. in. The dry gallon of United States
cu. in. Imperial gal. of Great Britain for dry and liquid measures
= 277.274 cu. in. Dry bushel of United States
= 2150.42 cu. in. Imperial bushel of Great Britain = 2218.192 cu. in.
60 seconds (sec.) = 1 minute (m.).
= 1 week (wk.).
= 1 month (mo.). 365 days
= 1 common year. 366 days
= 1 leap year.
ANGULAR OR CIRCULAR MEASURE
30 degrees = 1 sign (S.).
Apparently the sun makes an entire revolution of the earth in 24 hours,* and consequently travels 15° in 1 hour; therefore,
1 hour of time = 15° longitude.
MISCELLANEOUS TABLE. 12 units
= 1 dozen. 12 dozen
= 1. gross. 12 gross
= 1 great gross. 20 units
= 1 score. 24 sheets of paper
= 1 quire. 20 quires
= 1 ream. 196 lbs.
= 1 barrel of flour. 200 lbs.
= 1 barrel of pork. When a sheet of paper is folded into two leaves, or 4 pages, and a book made in this way, it is called a folio.
4.leaves is called a quarto.
12 leaves is called a duodecimo.