Overview

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. 1795 Excerpt: ...and annexed thereto, in its proper Column; and thus proceed from Station to Station, leaving your Object in the last Point you left, till you return to the first Station A. By By this Method your Stations are laid out to the beft Advantage, and two Men may do the Bufmefs of three, for one of thofe who chain may be your Object; but in Fore-Sights, you mull have an Object before you, bef1des two Chainmen. It was faid before, that a Surveyor mould have a Perlbn with him to carry the hinder End of the Chain, on whom he can depend: This Perfon fhould be expert and ready at taking Off-fets, as well as exact in giving a faithful Return of the Length of every Stationary Line. One who has fuch a.Perfon, and who ufes Back-Sights, will be able to go over near double the Ground he could at the fame Time, by taking Fore-Sights. But if a Surveyor has no fuch Perfon on whorn he C3n with Safety depend, hemuft take Fore-Sights, becaule of overfeeing the Chaining; for mould he take Back-Sights, he muft be obliged, after taking his Degree, to go back to the foregoing Station, to overfee the Chaining, and by this means to walk three Times over every Line, which is a Slavery not to be born. Or a Back and a Fore-Sight may be taken at one Station, thus; with the South of the Box to your Eye, obferve from B the Object A, and fet down the Degree in your Field-Book, cut by the South End of the Needle. Again, from B obfe1ve an Object at C, with the North of the Box to your Eye, and fet down the Degree cut by the South Point of the Needle, fo have you the Bearings of the Lines AB and BC; you may then let up your Inftrument at D, from whence take a Back-Sight to C, and a Fore-Sight to E; thus the Bearings may be taken quite round, and the ftationary Diftances being annexed to the...

Full Product Details

9781235883354

Table of Contents

Reviews

Author Information

Tab Content 6

Customer Reviews

Recent Reviews

Countries Available