ABSTRACT
Cherrapunji, Khasi Hills, India. (1906-40) Greenwich, London. (1880-1950)
THE TROPICAL INFLUENCE
In an age when Britain’s desire for trade was sending her ships and men over all the world it followed that as a matter of course scientific observers began to travel the same routes. In a surprisingly short time Survey departments were set up in the British colonies and geologists became essential members of exploring parties which examined the potentialities of the new regions. In this way the field of geological knowledge was widened rapidly. The new areas provided fresh features and also threw fresh light on old problems. Thus, the different balance that exists between fluvial and marine erosion in the tropics caused a healthy reconsideration of several erroneous assumptions on landscape evolution that had become engrained in the minds of European geologists. In the humid tropics the equivalent of the normal monthly rainfall of a locality in the English lowlands could fall in one hour. Moreover, the warm heavy rain greatly assists weathering, and
rocks, such as granite, which may form uplands in Britain may be degraded into lowlands in the wet tropics. The tremendous gorges, stupendous river-spates and great depth of rock-rotting impressed many early observers.
