This book gives an account of a method of determining the type composition of sandy deposits from the air by the nature of their reflection of radiant energy. The measured spectral luminance of a rock outcrop rela­ ti ve to the luminance of a standard is the basic property considered in this method. The spectral luminance factors p are measured by means of special instruments - a universal photometer, cinespectrograph, spectro­ visors, and other spectrometers. The measured values of P" of the investigated rocks are interpreted geologically with the aid of some methods of mathematical statistics so that a means of lithological mapping of sandy deposits from the air can be found. The importance of developing a method of determining the type composition of rocks, primarily sandy de­ posits, from the air stems from the extensive occurrence of deserts on the earth's surface. Sandy deserts occupy vast areas in the southern latitudes of the USSR and occur in western and central China, Pakistan, Iran, India, and other states. In these deserts there are numerous deposits of petroleum and gas, and a search for water is continuously in progress. Successful prospecting for the above minerals depends on a determination of the material composition of the sandy deposits in these deserts and the solution of several questions of recent tec­ tonics, paleogeography, and quaternary geology, the answers to which might also be given by a study of the dis­ tribution of lithological types of sands.