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ASIA. "YTEXT to Africa, we shall probably find in Asia, oldest of IN the Old World continents, a greater store of new facts presented to us, or, it may be, of old facts with changes in new features revealed by the light of modern continental scientific research, than in any other quarter of physiothe globe. It is in the realm of physical graphy. geography, and its collateral branches of science, that we have chiefly to mark important accessions of knowledge; and the knowledge thus acquired is, throughout the continent, given to us rather in the form of more exact information than as absolutely new discovery which might lead to any large correction of preconceived ideas. General Expansion of Exact Surveys. The progress of geodetic surveys in Russia had long ago extended across the European half of the great empire, Petersburg being connected with Tiflis on the southern slopes of the Caucasus by a direct system of triangulation carried out with the highest scientific precision. Petersburg, again, is connected with Greenwich by European systems of triangulation; and the Greenwich meridian has been adopted by Russia as the zero for all her longitude values. But beyond the eastern shores of the Caspian no system of direct geodetic measurement by first-class triangulation has as yet been possible, and the surveys of Asiatic Russia are separated from those of Europe by the width of that inland sea. The arid nature of the transCaspian deserts has so far proved an insuperable obstacle to those rigorous methods of geodetic survey which distinguish Russian methods in Europe, so that Russian geography in Central Asia is dependent on other means than that of direct measurement for the co-ordinate values in latitude and longitude for any given point. The astronomical observatory at Tashkent is adopted for the initial starting-point of the trans-Caspian triangulation of Russia; the triangulation ranks as second class only, and now extends to the Pamir frontier beyond Osh. The longitude of the Tashkent observatory has been determined by telegraph differentially with Pulkova as follows :—• h. m. s. In 1875 vid Ekaterinburg and Omsk. 2 35 52-151 ,, 1891 ,, Saratow ,, Orenburg 2 35 52'228 ,, 1895 ,, Kiew ,, Baku 2 35 51‘997 With these three independent values, all falling within a range of 0s’2 5, it is improbable that the mean value has an error as large as 0s'10. Exact surveys in Russia, based upon triangulation, extend as far east as Chinese Turkestan in longitude about Extent of °f Greenwich. In India geodetic triexact sur- angulation furnishes the basis for exact surveys veys in s far east as the eastern boundaries of Burma a As,a ' in longitude about 100° E. The years since 1875 have witnessed the forging of the final links in the great geodetic triangulation of India, so far as the peninsula is concerned. Further geodetic connexion with the European systems still remains to be accomplished. Since 1890 further and more rigorous application of the telegraphic method of determining longitudes differentially with Greenwich has resulted in a slight correction (amounting to about 2" of arc) to the previous determination by the same method through Suez. This last determination was effected through four arcs as follows :— I. Greenwich—Potsdam. II. Potsdam—Teheran. III. Teheran—Bushire. IY. Bushire—Karachi.

Each arc was measured with every precaution and a multitude of observations. The only element of uncertainty was caused by the retardation of the current, s which between Potsdam and Teheran (3000 miles) took 0 ’20 to travel; but it is probable that the final value can be accepted as correct to within 0s'05. The final result of this latest determination is to place the Madras observatory 2' 27" to the west of the position adopted for it on the strength of absolute astronomical determinations. But whilst we have yet to wait for that expansion of first-class geodetic triangulation which will bring Asia into connexion with Europe by the direct process Conaexioa of earth measurement, we have already effected between a topographical connexion between Russian and Russian Indian surveys which sufficiently proves that and ,ndiaa the deductive methods employed by both surveys' countries for the determination of the co-ordinate values of fixed points so far agree that, for all practical purposes of future Asiatic cartography, no difficulty in adjustment between Indian and Russian mapping need be apprehended. This connexion was effected near Lake Victoria during the Pamir Boundary Commission of 1895. The final values determined in longitude for the initial pillar of the boundary by the Russian and English surveyors respectively differed by about 1 'O" only, a difference which will never lead to serious difficulties in mutual map adjustment. In connexion with the Indian triangula- Extension tion minor extensions carried out on systems of geoinvolving more or less irregularity have been graphical pushed outwards on all sides. They reach surveysthrough Afghanistan and Baluchistan to the eastern districts of Persia, and along the coast of Makran to that of Arabia. They have long ago included the farther mountain peaks of Nepal, and they now branch outwards towards Western China and into Siam. These far extensions furnish the basis for a vast amount of exploratory, survey of a strictly geographical character, and they have contributed largely towards raising the standard of accuracy in Asiatic geographical surveys to a level which was deemed unattainable fifty years ago. There is yet a vast field open in Asia for this class of surveys. Whilst at the close of the 19th century Western Asia (exclusive of Arabia) may be said to be freed from all geographical perplexity, China, Mongolia, and Eastern Siberia still include enormous areas of which our geographical knowledge is in a primitive stage of nebulous uncertainty. Of scientific geographical exploration in Asia (beyond the limits of actual surveys) the period since 1870 has been so prolific that it is only possible to refer in barest outline to some of the principal ^^ors" expeditions, most of which have been directed either to the great elevated tableland of Tibet, or to the central depression which exists to the north of it. In Southern Tibet the trans-Himalayan explorations of the native surveyors attached to the Indian survey, notably pundits Nain Sing and Kishen Sing, Ind,an have added largely to our knowledge of the great plateau. Nain Sing explored the sources of the Indus and of the Upper Brahmaputra in the years 1865-67 ; and in 1874-75 he followed a line from the eastern frontiers of Kashmir to the Tengri Nor lake and thence to Lhasa, in which city he remained for some months. Kishen Sing’s remarkable journey in 1879-82 extended from Lhasa northwards through Tsaidam to Sachu, or Saitu, in Mongolia. He subsequently passed through Eastern Tibet to