MODERN MAPS From the middle of the 18th century to the early part of the 19th was a period which witnessed the beginning of regular topo graphical surveys in many countries. Thus, in France, Cassini de Thury commenced the first regular topographical map in The scale of this map was :86,400. In 1817 the Carte de France de l'etat major, on the scale of f :8o,000, was begun, but this was not finished until 1880. These were both engraved on copper.
In Great Britain the Ordnance Survey was founded in 1791; its original purpose was the construction of a map on the scale of 'in. to im., or 1:63,36o. The survey of Ireland on the scale of 6in. to im. was commenced in 1825. Great Britain and Ireland have been mapped on the scale of I :2,500, or about 25in. to im., excepting only waste and mountainous areas. Both the large-scale maps and the small-scale maps of Great Britain (fin., sin. and fin. to the mile), are revised periodically.
By the middle of the 19th century topographical maps of the various German States were complete. The Austrian :75,000 series was completed in 1889. The famous map of Switzer land, with which is associated the name of Gen. Dufour, was fin ished in 1865; it is on the scale of I :ioo,000. Generally speaking, we may say that during the 59th century all European States ex cept Russia had completed their small-scale mapping, and the sheets were, as a rule, printed from engraved copper plates. In India, Maj. James Rennell commenced the first reliable surveys of Bengal in 1764, and the Survey of India has, since that date, continued to map the Indian empire.
The scales adopted by the United States Geological Survey, which carries out the topographical mapping, are :62,50o, I :125,0m and :25o,000. The continent of Africa is slowly being surveyed on topographical scales, the early topographical surveys being mainly those along the international boundaries, needed for the partition of Africa, which began in International Map of the official title of this international undertaking is Carte du Monde au Millionieme, and references to it will generally be found under this title. It owes its origin to the initiative of Prof. A. Penck, who put forward the
project of a map of the world on a uniform scale at the Geograph ical Congress held at Berne in 1891. The scale proposed was one millionth of nature, equivalent to 'km. to i millimetre. The scheme and the scale were accepted by the congress, and an in ternational, but unofficial, committee was appointed for the pur pose of prosecuting the idea. This committee reported to suc cessive Geographical Congresses held in London in 1895, in Berlin in 1899 and in Washington in 1904, but slight progress was made.
An important step was, however, taken at the Geographical Congress held at Geneva in 1908. At this congress the delegates of the United States made a proposal for the definite standardiza tion of the map and for the drawing-up of fixed rules to govern its production. The geographical section of the British general staff took up the subject and an official conference was effected.
In Nov. 1909 the official conference assembled at the Foreign Office in London. The conference came to unanimous conclusions, and an account of it was published in a report issued by the British Government.
At the Geographical Congress at Rome in 1913 the scheme as formulated in London was accepted generally, but there was a feeling that a more comprehensive official conference was needed in order to put the matter before those countries not hitherto represented officially. An official conference was accordingly held in Paris in Dec. 1913. Thirty-four States sent representa tives, and, a very thorough examination was made of the London resolutions. In the main they were accepted, and the modifications made were of detail only. The Carte du Monde an Millionieme is now a world undertaking on lines accepted by practically all civilized countries.
The Paris Conference approved the establishment of a "bureau permanent," comprising a central office at the headquarters of the Ordnance Survey at Southampton, with a branch office at the Royal Geographical Society.
A third Conference was held in London in July, 1928, to decide some points of detail which had arisen since 1913. These were settled unanimously.