A complete treatise on practical land-surveying, in seven parts; . 46. A sector is any part of a circle bounded by an arc, andtwo radii. 47. A quadrant is the fourth part of a circle, or a sectorbounded by an arc and two radii at right angles to each other ;as C D B. Corol. Hence a right angle is said to contain 90°. Note.—All Definitions and Rules should be committed to memory. GEOMETRICAL PROBLEMS. PROBLEM I. To bisect a given Line A B, in n From A and B as centres, with any radius greater than halfA B, in your compasses, describe arcs cutting each other inm and n. Draw the line m C n, and i
A complete treatise on practical land-surveying, in seven parts; . 46. A sector is any part of a circle bounded by an arc, andtwo radii. 47. A quadrant is the fourth part of a circle, or a sectorbounded by an arc and two radii at right angles to each other ;as C D B. Corol. Hence a right angle is said to contain 90°. Note.—All Definitions and Rules should be committed to memory. GEOMETRICAL PROBLEMS. PROBLEM I. To bisect a given Line A B, in n From A and B as centres, with any radius greater than halfA B, in your compasses, describe arcs cutting each other inm and n. Draw the line m C n, and it will bisect A B in 0. 12 LAND-SURVEYING. (Part. J. PROBLEM II. To bisect a given Angle A B From the point B with any radius, describe the arc A A and C with the same, or any other radius, make theintersection m. Draw the line B m, and it will bisect the aDgleA B C, as required. PROBLEM III. To draw a Line parallel to a given Line A B, at a given Distance. C i- o -N* m TO. From any two points, m and n, in the given line, with thegiven distance as a radius, describe the arcs r and o. Draw C Dto touch these arcs, without cutting them, and it will be parallelto AB. Note.—This problem may be more readily performed by a parallel ruler. Part I.) LAND-SURVEYING. 13 PROBLEM IV. To erect a Perpendicular from a given Point C, near the Middleof a given Line A B. ?v m. n B On each side of the point C, take two equal distances, C mand C n ; from m and n as centres, with any radius greater thanC m or C n, describe two arcs cutting each other in r. Drawthe line C r, and it will he the perpendicular required. PROBLEM V. To erect a Perpendicular from a given Point C, near the Endof
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