SECT. VI. Containing the nature of Off-sets and Intersections; the Methods of enlarging, or diminishing, and connecting Maps; the Variation of the Compass, and its Uses in Surveying; the whole concluding with some necessary Directions concerning Surveys in general. OF OFF-SETS. IN In taking surveys it is unnecessary and unusual ‘to make a station at every angular point, because the field-work can be taken with much greater expedition, by using off-sets and intersections, and with equal certainty; especially where creeks, &c. bound the survey. Off-sets are perpendicular lines drawn or measured from the angular points of the land, that lie on the Let the black lines represent the boundaries of a farm or township: and let 1 be the first station, then if you have a good view to 2, omit the angular points between 1 and 2, and take the bearing and length of the stationary line 1, 2, and insert them in your fieldbook: but in chaining from 1 to 2, stop at d opposite to the angular point a, and in your field-book insert the distance from 1 to d, which admit to be 4C. 25L. as well as the measure of the off-set ad, which admit to be 1C. 12L. thus: by the side of your field-book in a line with the first station, say at 4C. 25L. L. 1C. 12L. that is, at 4C. 25L. there is an off-set to the left hand of 1C. 12L. This done proceed on your distance line to c, opposite to the angle b, and measure eb, supposing then 1 e to be 7C. 40L. and eb 3C. 40L. say (still in a line with the first station in your field-book) “at 7C. 40L. L. 3C. 40L." that is, at 7C. 40L. there is an off-set to the left of 3C. 40L. proceed then with your distance line to f, opposite to the angle c, and measure fc; suppose then 1 f to be 13C. and fe 1C. 25L. say in the same line as before, at 13C. L. 1C. 25L. Then proceed from ƒ to 2, and you will have the measure of the entire stationary line 1, 2, which insert in its proper column by the bearing. In taking off-sets, it is necessary to have a perchchain, or a staff of half a perch, divided into links for measuring them; for by these means the chain in the stationary line is undisturbed, and the number of chains and links in that line from whence, or to which, the off-sets are taken, may be readily known. Having arrived at the second station, if you find your view will carry you to 3, take the bearing from 2 to 3, and in measuring the distance line, stop at l opposite g; admit 2l to be 4C. 10L. and the off-set lg 1C. 20L. then in a line with the second station in your field-book, say at 4C. 10L. R. 1C. 20L. that is the off-set is a right-hand one of 1C. 20L. Again at m, which suppose to be 10C. 25L. from 2; take the offset mh of 1C. 15L. and in a line with the second station, say at 10C. 25L. R. 1C, 15L. In the same line when you come to the boundary at i, insert the distance 21, 13C. 10L. thus, at 13C. 10L. 0; that |