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IV. 

 TOPOGRAPHICAL SURVEYS. 



The Topographical and Revenue Surveys serve to furnish the 

 details required for filling up the outline supplied by the fixed points 

 of the triangulation, the former being confined mainly to the Native 

 States, and non-regulation British districts, of small importance from 

 a revenue point of view, while the Revenue Surveys deal with the 

 more productive and valuable tracts. As has been appropriately said, 

 it is their function to supply flesh and blood to the skeleton provided 

 by the triangulators. But while the Trigonometrical Survey has 

 had to be conducted regularly throughout on a fixed plan, both the 

 Topographical and Revenue operations have to be taken up on 

 varying scales to suit local requirements and conditions. The 

 standard scale of the Topographical Survey is 1 inch to the mile, 

 but where the work has to be executed very quickly the scale is 

 reduced to -J or to J of an inch to the mile, as in trans-frontier 

 regions ; on the other hand, in British territory it is sometimes 

 increased to 2 inches, and generally to 4 inches for Forest Surveys. 

 The Revenue Surveys are on scales of 4, 16, and 32 inches to the 

 mile, and sometimes larger scales. These two classes of operations 

 have covered the greater portion of the expanse of British India 

 and the Native States, which have thus been, or are being, practically 

 mapped out on the scale and in the manner most appropriate to 

 the general purposes of administration. The accuracy of the 

 work has necessarily varied greatly according to circumstances. 

 Some of the earlier topographical surveys partook more of the 

 nature of rough and hasty geographical reconnaissances, but the 

 more recent surveys have been carried out on more rigorous 

 principles, and with greater regard for completeness and precision. 

 Since the close of the Punjab war in 1847, and the publication 

 of the " Manual of Surveying for India " a few years later, by 

 Captains Smyth and Thuillier, there has been an ever-increasing 

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