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MEASURES OF VOLUME.

§ 37. Cubic Measure. 1000 cubic millimeters (cu mm) = 1 cubic centimeter (cu cm). 1000 cubic centimeters =1 cubic decimeter (cu dm) =1 liter. 1000 cubic decimeters

=1 cubic meter (cu m) = 1 ster.

§ 38. Wood Measure.
10 decisters (ds) = 1 ster (s).
10 sters = 1 dekaster (Ds).

$ 39. As the units of cubic measure form a scale of thousands, in writing numbers expressing volume three decimal places must be allowed for each denomination.

Thus, 427 cu m 29 cu dm 3 cu cm are written 427.029003 cu m. § 40. As the units of wood measure form a scale of tens, only one decimal place is needed for each denomination.

Thus, 7 dekasters 5 sters 6 decisters are written 75.6 sters.

$ 41. Examples for the Slate. 36. Express the following in cubic meters and add them: 7 cu. meters 40 cu. decimeters; 5 cu. meters 3 cu. decimeters 19 cu. centimeters; 25 cu. centimeters 49 cu. millimeters.

37. How many cubic meters of earth must be removed to dig a cellar 14.5 m long, 4.6 m wide, and 2.3 m deep ?

38. At $1.25 a cubic meter, what will it cost to dig a trench 75.5 m long, 2.2 m wide, and 1.8 m deep ?

39. How many loads of earth, each filling 2.25 cum, will fill a space 15.4 m long, 12 m wide, and 4.5 m deep ?

40. If a cubic centimeter of gold is worth $12.50, what is the value of a brick of gold 2.4 cm long, 1.3 cm wide, and 0.75 cm thick ?

41. If I burn 27 sters of wood in the three winter months, what must be the length of a pile 1 meter wide andmeter high to last a month, and what will it cost at $ 2.25 a ster ?

MEASURES OF CAPACITY.

§ 42. The primary unit of measure for all substances that can be poured into a dish or box is the liter.

§ 43. A liter is equal in volume to one cubic decimeter. § 44. Larger and smaller measures are derived from the liter in the same way that longer and shorter measures are derived from the meter, that is, by taking decimal multiples and subdivisions.

§ 45. Liquid and Dry Measures.

1 milliliter

1 milliliter (ml) = 1 cu cm.
10 milliliters = 1 centiliter (cl).
10 centiliters = 1 deciliter (dl).
10 deciliters = 1 liter (1) = 1 cu dm.
10 liters = 1 dekaliter (DI).
10 dekaliters = 1 hektoliter (Hl).
10 hektoliters = 1 kiloliter (KI). = 1 cu m.

NOTE. The milliliter is employed in computations, but rarely, if ever, in actual measurements. Chemists and druggists use cubic centimeters instead of milliliters.

§ 46. Examples for the Slate. 42. If one hektoliter of kerosene costs $20, what is the price of a liter?

43. What must be paid for 2.5 liters of milk each day for a week, at 7 cents a liter?

44. From a vessel containing 1 hektoliter of syrup, 25 liters were drawn out. How many liters remained ? .

45. How many hektoliters of oats can be put into a bin that is 2 m long, 1.3 m wide, and 1.5 m deep?

46. What must be the length of a bin 1 meter wide and 1 meter deep, to contain 4500 liters of grain ?

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§ 47. The primary unit of weight is the gram.

§ 48. A gram is the weight of one cubic centimeter of pure water at the temperature of 4 degrees centigrade (= 39.2 degrees Fahrenheit), at which temperature water has its greatest density.

§ 49. Larger and smaller weights are derived from the gram by taking decimal multiples and subdivisions.

$ 50. Weights. 10 milligrams (mg) = 1 centigram (cg). 10 centigrams = 1 decigram (dg). 10 decigrams =1 gram (g) = wt. of 1 cu cm of water. 10 grams = 1 dekagram (Dg). 10 dekagrams = 1 hektogram (Hg). 10 hektograms = 1 kilogram (K) = wt. of 1 cu dm of water. 10 kilograms = 1 myriagram (Mg). 10 myriagrams = 1 quintal (Q).

10 quintals = 1 metric ton (T.) = wt. of 1 cu m of water. Note I. The gram, kilogram, and metric ton are the only units used in actual weighing, except by jewellers, druggists, and those who weigh very small or very expensive articles, like gold or powerful medicines.

NOTE II. The kilogram is generally called the kilo. The kilo is the unit of weight for weighing common articles, such as sugar, tea, etc.

NOTE III. The metric ton is used to weigh very heavy articles, like hay, coal, etc.

§ 51. Examples for the Slate. 47. At $0.60 a kilo for honey, what is the cost of 5.15 kilos ?

48. At $ 11 per T. for coal, what will the coal cost to keep a fire one week if 30 kilos are burnt each day?

49. What weight of mercury will a vessel contain whose capacity is 10 cu cm, mercury being 13.5 times as heavy as water ?

50. If marble is 2.7 times as heavy as water, what is the weight of a pedestal 1 meter square at each end and 2 meters high ?

§ 52. Table of Equivalents. The equivalents here given agree with those that have been established by Act of Congress for use in legal proceedings and in the interpretation of contracts.

1 inch = 2.540 centimeters. 1 centimeter = 0.3937 inch.
1 foot = 3.048 decimeters. 1 decimeter = 0.328 foot.
1 yard = 0.9144 meters.

1 meter = 1.0936 yds. = 39.37 in. 1 rod = 0.5029 dekameters. 1 dekameter = 1.9884 rods. 1 mile = 1.6033 kilometers. 1 kilometer = 0.62137 mile. 1 sq. inch = 6.452 sq. centimeters. 1 sq. centimeter = 0.1550 sq. inch. 1 sq. foot = 9.2903 sq. decimeters. 1 sq. decimeter = 0.1076 sq. foot. 1 sq. yard = 0.8361 sq. meter. 1 sq. meter = 1.196 sq. yards. 1 sq. rod = 25.293 sq. meters. 1 ar = 3.954 sq. rods.. 1 acre == 0.4047 hektar.

1 hektar = 2.471 acres. 1 sq. mil2 = 2.590 sq. kilometers. 1 sq. kilometer = 0.3861 sq. mile. 1 cu.inch = 16.387 cu.centimeters. 1 cu. centimeter = 0.0610 cu. inch. 1 cu. foot = 28.317 cu. decimeters. 1 cu. decimeter = 0.0353 cu. foot. 1 cu. yard = 0.7645 cu. meter. 1 cu. meter = 1.308 cu. yards. 1 cord = 3.624 sters.

1 ster = 0.2759 cord. 1 liquid quart = 0.9463 liter. 1 liter = 1.0567 liquid quarts. 1 gallon = 0.3785 dekaliters. 1 dekaliter = 2.6417 gallons. 1 dry quart = 1.101 liters. 1 liter = 0.908 dry quart. 1 peck = 0.881 dekaliter. 1 dekaliter = 1.135 pecks. 1 bushel = 3.524 dekaliters. 1 hektoliter = 2.8375 bushels. 1 ounce av. = 28.35 grams. 1 gram = 0.03527 ounce av. 1 pound av. = 0.4536 kilogram. 1 kilogram = 2.2046 pounds av. 1 ton (2000 lbs.) = 0.9072 met. ton. 1 metric ton = 1.1023 tons. 1 grain Troy = 0.0648 gram. 1 gram = 15.432 grains Troy. 1 ounce Troy = 31.1035 grams. 1 gram = 0.03215 ounce Troy. 1 pound Troy = 0.3732 kilogram. 1 kilogram = 2.679 pounds Troy.

EQUIVALENTS.

§ 53. To change numbers in the metric system to equivalents of the old system :

Examples. 51. In 48 meters how many feet ?

52. If you travel 50 kilometers in a day, how many miles do you travel ?

53. Change 18 hektars of land to acres.

54. How many inches long is an insect that is 5.2 centimeters long?

55. How many pounds av. are there in 85.6 kilos of salt ? 56. How many gallons are there in 24 kiloliters ? 57. In 20 metric tons how many tons ?

$ 54. To change numbers in the old system to equivalents of the metric system :

Examples 58. Change 25 miles to kilometers. 59. In 200 acres are how many hektars ?

60. How many liters will a cistern hold that measures on the inside 5 feet in length, 4 feet in width, and 4 feet in height?

61. In 3 rods how many meters ?
62. Change 18 qt. 1 pt. to liters.
63. In 1 lb. 7 oz. 18 pwt. of gold, how many grams ?

64. What is the weight of a barrel of four (196 lbs.) in kilograms?

§ 55. Approximate Equivalents. The equivalents here given are accurate enough for most purposes, and are easy to remember. A decimeter = 4 inches. | A ster = 4 of a cord. 13 ft. 33 in.,

_11.06 liquid qt, A meter

A liter lor 1to yards.

Tory of a dry qt. A dekameter = 2 rods.

A dekaliter = 1 peck and 1 qt. A kilometer = of a mile.

A hektoliter = 24 bushels. 'S4 sq. rods,

A gram = 154 grains. An ar

or do of an acre. | A kilogram = 2} pounds av. A hektar = 2 acres. A metric ton = 2200 pounds av.

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