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THE following pages were drawn up for the use of the junior officers of the Royal Engineers, and those of the Honourable East India Company's Service, in their course of instruction in Trigonometrical Surveying and Practical Astronomy at this establishment, of which branch of their studies I have for some time had the superintendence.

My original intention was to have had them lithographed for distribution among the officers; but I have been since led to the resolution of publishing them in their present form, from their having swelled to a size beyond what I at first contemplated; and also from the total want experienced, during the period occupied in compiling them, of any practical English work on Geodesical Operations, extending beyond the mere elementary steps of Land Surveying. Of this class there are several very useful publications, containing instruction in all the necessary detail, to some of which references are made for information respecting the preliminary knowledge of the construction and use of the instruments most generally employed, as well as to the French authors on Geodesy, whose works I have consulted.

Of the extensive and scientific Geodesical Operations described in these latter works, the present Treatise professes to give nothing beyond a brief outline, as their detailed account would be far too voluminous to be condensed in so small a compass.

The cadets at Woolwich and Addiscombe are taught the use of the Chain and Theodolite, and to calculate the contents of the different portions into which the ground is divided by natural and artificial boundaries; they are also rendered conversant with Plane Trigonometry and Mensuration, and with sufficient Spherical Trigonometry for the solution of the ordinary cases of Spherical Triangles. Such preliminary knowledge is consequently assumed as being already acquired. It is, however, in the power of any individual to make himself master of the necessary theoretical part of this knowledge, by the study of one or other of the numerous excellent works on Trigonometry and Mensuration; and the practice of Land Surveying can be acquired in a few weeks in the Field, under any competent Instructor, or even without this assistance, by the careful study of some elementary work on the subject.





In consequence of finding, on my recent return to England, that this work had been for some time out of print, and that considerable portions had been extracted by different authors, a second edition has been prepared, in which, beside many alterations, improvements, and omissions of parts since deemed not sufficiently practical, will be found a separate chapter devoted to Surveying in the Colonies, with reference to the marking out of waste lands for future occupation; the result of nearly ten years' experience obtained during the superintendence of the Survey of South Australia.


April, 1850.

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