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. 1827 edition. Excerpt: ... COMMENCEMENT OF A TOPOGRAPHICAL SURVEY UNCONNECTED WITH A TRIGONOMETRICAL SURVEY. We will first suppose the topographical survey of a small portion of country is to be taken unconnected with a trigonometrical survey. In this instance, should the scale be rigidly prescribed, one line, called the base of the ...
Read More
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. 1827 edition. Excerpt: ... COMMENCEMENT OF A TOPOGRAPHICAL SURVEY UNCONNECTED WITH A TRIGONOMETRICAL SURVEY. We will first suppose the topographical survey of a small portion of country is to be taken unconnected with a trigonometrical survey. In this instance, should the scale be rigidly prescribed, one line, called the base of the survey, must be measured; and, since it is the only one which requires to be so, (except in some particular cases, as will be explained hereafter, ) the surveyor will not object to bestow great care and attention, in order to obtain its exact length. Should however any error be committed in the measurement, it will not, as in surveys constructed entirely from measured lines and angles, communicate itself to the whole work, but merely to the scale of the plan, which can be corrected before the plan itself is completed; for, since the remaining horizontal lines, and the angles which they contain, are not measured, but all objects are determined, on the ground, by means of lines of sight drawn in their true vertical planes, no distortion of parts can take place; the whole will be in exact geometrical proportion with the country represented. If the scale on which the plan is to be drawn be rigidly prescribed, it will generally be necessary to commence by measuring the base; but, should this not be the case, and the features of the ground be such, that from two or three high summits, a considerable portion of what is to be surveyed can be seen, it will be more convenient to commence the survey at once from these points, and to measure a base subsequently, upon a piece of ground convenient for that purpose. In choosing the best situation for a base, the surveyor should attend to the following directions: 1. Let the base be situated in a level plane, .
Read Less
Add this copy of A Practical Treatise on Topographical Surveying and to cart. $18.95, new condition, Sold by Paperbackshop rated 4.0 out of 5 stars, ships from Bensenville, IL, UNITED STATES, published 2019 by Hardpress Publishing.
Add this copy of A Practical Treatise on Topographical Surveying and to cart. $30.83, new condition, Sold by Booksplease rated 4.0 out of 5 stars, ships from Southport, MERSEYSIDE, UNITED KINGDOM, published 2019 by Hardpress Publishing.
