MEASURES OF EXTENSION 231. The unit is the meter, about 39.37 inches. = = 100 sq. millimeters = 100 sq. centimeters = 100 sq. decimeters = 100 sq. meters = = 100 sq. dekameters = = = = = 19. 9278 rd. = = .621+mi. 6.21+ mi. 1 sq. centimeter (sq. cm.). 1 sq. decimeter (sq. dm.). 1 sq. meter (sq. m.). 1 sq. dekameter (sq. Dm.). 1 sq. hektometer (sq. Hm.) 100 sq. hektometers = 1 sq. kilometer (sq. Km.). NOTE.-In measuring land, the square meter is called a centare (ca), the square dekameter an are (a), and the square hektometer a hektare (Ha). 232. The unit in both liquid and dry measures is the liter, and it contains a cubic decimeter. Liquid Dry 233. The unit is the gram, which is the weight of a cubic centimeter of distilled water at its greatest density (4° C). REDUCTION 234. Reduction descending and ascending may be performed in the Metric System as in the other systems; but, since the scale is decimal, the reduction may be made by simply moving the decimal point. EXAMPLES 1. Reduce 40000 dm. to Km. PROCESS: 40000 dm. = 4.0000 Km. = 4 Km., result. 2. Reduce 6 Hm. 4 Dm. 2 m. to m. PROCESS: 6 Hm. 4 Dm. 2 m. = 642 m., result. 3. Reduce 48365 dm. to higher units. PROCESS: 48365 dm. = 4 Km. 8 Hm. 3 Dm. 6 m. 5 dm., result. NOTE. To divide by 10 repeatedly will give successively the remainders 5, 6, 3, etc., and the result will be as given above. Exercise XXX 1. When was the Metric System adopted by France? How many years elapsed before it was legalized in the United States? How extensively is it used (a) in business, (b) in science? What advantage has it over the older systems? 2. How was the length of the meter fixed? How was the liter fixed? How was the gram fixed? 3. Define milli, centi, deci; deka, hekto, kilo, myria. Reduce: 4. 4735 cm. to higher units. 5. 7 Mm. 8 Km. 6 Hm. 5 Dm. 4 m. to mm. 6. 236220 ft. to Dm. 7. 4.003 Dm. to mm. 9. 540000 sq. cm. to sq. m. 10. 75 cu. Km. to cu. m. 16. 5863 cg. to higher units. 11. 8 Hl. 4 1. to dl. 12. 75 bu. to Dl. 13. 7 Hl. to gal. 14. 6 Dg. to mg. 15. 50 Mg. to lb. av. 17. Find the weight in grams of a cu. dm. of iron (sp. gr. 7.21). NOTE.-The specific gravity (sp. gr.) of a substance is the ratio between its weight and the weight of an equal volume of water, 18. What is the weight in pounds of a cu. m. of ice (sp. gr. 0.92)? 19. The Eiffel tower at Paris is 300 m. high. How many feet higher is it than the Washington monument (555 ft. high)? 20. Find the cost of excavating 6.25 cu. m. of earth, at $0.0015 per cu. dm. 21. The nickel 5-cent piece is 20 mm. in diameter. How many laid side by side will reach 2020 Dm.? 22. A nickel 5-cent piece weighs 5 g.; a silver halfdollar weighs 12.5 g.; what is the combined weight of $12 in nickels and $40 in silver half-dollars? 23. If I buy 500 bu. of wheat at 75¢ a bushel, and sell it at $3 per Hl., do I gain or lose? 24. A merchant bought cloth at $1.15 per meter and sold it by the yard at a profit of 20%. How much did he get for it per yard? 25. A physician put up 500 dg. of quinine into pills of 8 cg. each; how many pills were there? 26. Find the capacity in Hl. of a barn 5 m. long, 4 m. wide, and 3 m. deep. 27. What per cent. of 185 Dg. is 740 dg.? 28. A room is 5.2 m. long, 4.5 m. wide, and 3.2 m. high. What will be the cost of plastering it at 35 cents per sq. m.? XI. SPANISH LAND MEASURES 235. The old Spanish land measures are still used in Texas, and to some extent in New Mexico and in the southern part of California. These places were originally settled by the Spanish. The most important terms used are these: vara, labor, and league. 236. The vara (vr.), corresponding nearly to our yard, is the unit in linear measure. The vara was divided into three equal parts called piés (feet), and the pié was divided into twelve equal parts called pulgadas (inches). pié and the pulgada, are not much used in Texas. The |