The Reign of Queen Victoria (Volume 1); A Survey of Fifty Years of Progress (Paperback)

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. 1887. Excerpt: ... and once for all. The scales finally adopted for the survey, and upon which the maps are now being published, are: (1) the town map, or 10-56 feet to a mile, on which one inch represents 500 inches as measured on the ground; (2) the 25-inch, or parish map, sVir' which is the true cadastral survey, agreeing as regards scale with the recommendations of the Brussels Conference of 1853: on this scale the area of every parcel of land is computed and published, either separately or on the plan itself, and a square inch represents very nearly an acre; (3) the county map, six inches to a mile, -n, on which the form of the ground is shown by contour lines at regular vertical intervals; and (4) the general, or military map of the country, one inch to a mile, nisTj, which is published in three editions--one showing only the rivers, roads, railways, canals, &c.; another representing the undulations of the ground by contour lines; and a third with the hills shown in a pictorial manner, by vertical lines or hachures. We must now glance at the processes by which the maps are produced, and the first step is the very important one of ascertaining the boundaries of the civil divisions of the country--counties, parishes, &c. This is the special care of a Boundary Office in London, which has in many ways rendered invaluable services to the State; and it may be remarked that no private boundaries are shown as such on the plans. The original survey and manuscript plan are made on the j.-1, scale; the great triangulation is broken up into secondary triangulation, and so on, until triangles of a convenient size for measurement are obtained. Each of these smaller triangles is allotted to a surveyor, who measures the sides, without knowing their computed lengths, and all the de...