ON THE LAMBERT CONFORMAL PROJECTION AS APPLIED IN CHINA

Abstract

In the last instalment of this paper it was explained that, owing to the immense size of the country, the co-ordinate system adopted by the Central Land Survey for the mapping of China consists of a number of zones bounded by parallels of latitude, the survey in each zone being based on the Lambert conical orthomorphic projection. The great extent of each zone in longitude, some sixty-five degrees, necessitated the development of series which would converge reasonably quickly, and, for this purpose, series were obtained in which a vertical distance between the parallel passing through the given point and the central parallel was used instead of the co-ordinates themselves. The series already given provided for the conversion of geographical co-ordinates into rectangulars and the inverse problem, while the present instalment deals with the scale factor and the transformation of co-ordinates from one zone to another, concluding with some numerical examples.