THE USE OF AIR PlIOTOGRApHS BY THE ORDNANCE SURVEY

Abstract

During the last year, the Air Survey Section, Field Division, Ordnance Survey, have had many visitors. Most of them have been surprised at what they have seen: some at the fact that we are able to make so much use of air photographs even in the largest scale surveys, and some at the small amount of information we seem able to extract from them. This paper is an attempt to give in some detail the ways in which air photographs are used to solve the problems of the Ordnance Survey, why they are used and their limitations for our purposes.