tending north and south is called a range; a series extending east and west is called a tier. Ranges are numbered east and west from the principal meridian; tiers are numbered north and south from the base line. A township is designated by the number of the tier and the number of the range in which it is located. Thus, township marked A, Fig. 1, is designated T. 3 N., R. 2 E., read township three north, range two east, which means that A is in the third tier north of the base line and in the second range east of the principal meridian. 18. A township is divided into sections approximately 1 mile square and numbered as shown in Fig. 2, beginning at the northeast corner. 19. A section is divided into quartersections, and the township, section, and quarter-section corners are permanently N.ź of Sec. 12 N.E. of marked. Quarter-sections may be subdivided, if desired, into half 6 5 4 3 2 / 78 18 17 16 15 14 13 19 20 21 22 23 24 30 29 28 27 26 25 31 32 33 34 35 36 Fig. 2. SWS.E.4 of quarter-sections and quarter-quarter-sections. 1. How many square miles are there in a township? 2. How many acres are there in a section? in a half-section? in a quarter-section? in a quarter-quarter-section? In Examples 3-8 make drawing as in section 17 and locate with respect to the principal meridian and the base line: * Townships and sections would be exact squares if it were not for the fact tha the meridians converge; that is, all north and south lines meet at the North Pole. 9. Read N.W., Sec. 12, T. 3 N., R. 1 W. 10. Read S. 1, Sec. 30, T. 2 N., R. 4 W. 11. Read W., Sec. 10, T. 2 S., R. 3 W. Make drawing as in section 19, and locate each of the following tracts of land; give the number of acres in the tract: 12. S. of N.W. 4. 14. S.E. of N.E. . 13. W. of S.E. . 15. S.W. of N.W. 4. METRIC SYSTEM 20. The metric system of weights and measures has been adopted by nearly all the countries of Europe and South America and by Mexico. Its use is permitted in the United States, and even required in certain work of the departments of the Government, such as the medical work of the Navy and the War Departments. It is the legal system of Porto Rico and the Philippines. 21. The fundamental unit of the metric system is the meter - the unit of length. From this the units of capacity (liter) and weight (gram) were derived. All other units are the decimal subdivisions or multiples of these. The three units named are simply related; thus: A liter is a cube .1 of a meter on an edge. A gram is the weight of a cube of pure water .01 of a meter on an edge at the greatest density of water, 39.2° Fahrenheit. 22. The metric tables are formed by combining the words "meter," "gram," and "liter" with the six prefixes here shown: 23. The primary unit of length is the meter; it is equal to 39.37 10 millimeters (mm) = 1 centimeter (cm) = 0.3937 in. 25. A quantity expressed in different metric units may be expressed and read without reduction in any denomination desired, or in more than one denomination; just as we now express a sum of money made up of $7000, $25, 6 d., 5, 2 m., in one denomination, $7025.652, which is sometimes read 7025.652 dollars, and sometimes seven thousand twenty-five dollars, sixty-five cents, two mills. Thus, 4Km 6Dm 5m 4cm 2mm may be expressed 4065.042m, and read four thousand sixty-five and forty-two thousandths meters, or 4 kilometers, 65 meters, 42 millimeters. 26. The metric system is a decimal system and therefore reductions from one denomination in it to another may be made by simply moving the decimal point to the right or to the left. 1.825m, = 638mm. Thus, 1825mm = 182.5cm 18.25dm = Exercise 6 Read: 1. 7Km in hectometers; in dekameters; in meters. 7. 4m 3cm in centimeters; in meters. 8. 2Dm 6m 5cm in meters. Write: 10. 25Km in meters. 1 Sq. Inch 1 Sq. Cm. 28. 9. 4Km 65m 375min in meters. II. 375mm in meters. 12. 4356m in kilometers. 13. .075m in millimeters. 14. 1425.62m in kilometers, meters, and millimeters. 27. In square measure the units are squares whose sides are the units of length, as in our system. For land measure a square 100 meters long called an are (meaning "area") is the unit. Table of Measures of Surface 29. In square measure in the metric system 100 units of any denomination make one of the next higher denomination; therefore, reductions from one denomination to the next higher or lower may be made by moving the decimal point two places to the left or two places to the right. Exercise 7 Express: I. 4am in square decimeters; in square centimeters. 2. 5adm in square centimeters; in square millimeters. 3. 654dm in square meters. 4. 1454mm in square meters. 5. 4am 6adm in square meters; in square decimeters. 6. 89m 69mm in square meters; in square millimeters. 7. 142a in hectares. 30. In cubic measure the units are cubes whose edges are the linear units. The cubic meter (sometimes called the stere, meaning "solid") is the unit of volume. 1 Cu. Inch 31. Table of Measures of Volume 1000 cubic millimeters (cmm) = 1 cubic centimeter (ccm) Cu 'Cm. = 1 cubic meter (cbm), or stere (s) = 35.315 cu. ft. |