Elements of surveying and levelling; with descriptions of the instruments and the necessary tables

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1871 Excerpt: ...180. Note.--The above principles are deduced, under the supposition that the two courses are both run from the same angular point. Hence, if it be required to apply these rules to two courses run in the ordinary way, as we go around the field, the bearing of one of them must be reversed before the calculation for the angle is made. EXAMPLES. 1. The bearings of two courses, from the same point, are N 37 E, and S 85 W: what is the angle included between them? Ans. 132. 2. The bearings of two adjacent courses, in going round a piece of land, are N 39 W, and S 48 W: what is the angle included between them? Ans. 87. 3. The bearings of two adjacent courses, in going round a piece of land, are S 85 W, and N 69 W: what is the angle included between them? Ans. 154. 4. The bearings of two adjacent courses, in going round a piece of land, are N 55 30' E, and S 69 20' E: what is the angle included between them? Ans. 124 50'. Laying Out And Dividing Land. 103. The surveyor is often required to lay off a given quantity of land, in such a way that its bounding lines shall form a particular figure, viz., a square, a rectangle, a triangle, s &c. He is also often called upon to divide given pieces of land into parts containing given areas, or, into areas bearing certain relations to each other. The manner of making such divisions must always depend on a skilful and judicious application of the principles of geometry and trigonometry to the particular case. For example, if it were required to lay out an acre of ground, in a square form, it would be necessary to find, by calculation, the side of such a square, and then trace, on the ground, a figure bounded by four equal sides, at right angles to each other. PROBLEM L 104. To lay out a given quantity of land in a square fo...