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MAP MAINTENANCE,POLICY AND TECHNIQUE
Abstract:Abstract

Introduction.—Although much has been written on the various branches of surveying, few text-books do more than give the problem of Map Maintenance a passing mention. It is true that probably the major problem of the surveyor, when considering the world as a whole, is the urgent need of any sort of accurate map for most of its surface, yet at the same time quite considerable areas have already been surveyed, and the maintenance of these areas forms a very formidable problem in itself. Moreover, it is not generally realized that problems of maintenance necessitate a complete reorientation of technical outlook in comparison with questions of an initial survey. Clearly, when maps are being made in the first instance, the primary requirement is an adequate framework, whose main essentials are accuracy; rigidity and permanence. The filling in of the topographical detail and the final reproduction are matters of necessarily secondary importance. Furthermore, as the time required for the field work is large in comparison with the office stages, there is little actual or apparent gain in reducing the time taken on drawing and reproduction. In these circumstances the problem of an initial survey is essentially mathematical in its technique, little attention being required for the final stages of drawing and reproduction, which can be carried out, by craftsmen, at the unhurried pace which it has been their privilege to maintain in the past.
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