Calcutta Geographical Review March & June 1946

To the east of Benares is the eastern country to the south of Mahismati (identified with Mandhata on the Narmada) is the Deccan to the west of Devasabhd is the western country to the north of Prthudaka (modern Pehoa about 14 miles west of ThAnesvar) is the northern country and the tract lying between the confluence of Jumna and the Ganges is called the Antarvedi. [...] This was the same story in the whole valley of Tigris and Euphrates and in the Assyrian highlands before the Christian era in the arid plains of Palestine and Syria during the Biblical times in the hill-slopes of Greece during the Hellenic civilisation in the fertile plains of Carthage behind the Atlas after the Punic Wars and Moorish invasions in the fertile plains of Persia at the end of Rom [...] Thus while in the latter case the drainage pattern is mainly dependent upon the nature of the surface and subsurface strata the amount of precipitation and the gradient of the land the development of a system of erosion gullies is governed by the relative erodibility of the surface and sub-surface soil the amount of surface run off and the slope of the land. [...] In the formative period of the soil under the protective cover of virgin forests and grasses the resistance to erosion exceeds the erosive force of water and undoubtedly the causes of excessive rates of soil erosion can be attributed to any artificial interference in the edaphic equilibrium which lessens the power of resistance of soil cover and increases the erosive force of running water. [...] As the velocity of the run-off running from the upper reaches of the watershed down to the point of egress is hydro-dynamically dependent upon the declivity of the land it is obvious that the greater the slope of the land the greater the velocity of run-off the less the time available for subsoil absorption and. greater the suface run-off will be in volume with increasing ravages of soil ero