Light and Colour

Abstract

DR. HOUSTOUN'S book deals with wide aspects of the science of light and colour, and will be found of interest by photographers and medical students as well as by members of the public generally. There is an excellent chapter on invisible rays, including a description of Prof. Rankine's method of wireless telephony and Dr. Fournier's optophone, by which a blind man is able to read ordinary printed matter, such as books and newspapers. A very clear and simple account of the X-ray spectrometer is included, and also an account of the current views of the structure of the atom. Primary and complementary colours are described by the author, who gives the usual table of complementary colours- that of Helmholtz-while he states that Helmholtz is not so definite on the subject as is generally supposed: he does not give the defects of Helmholtz's methods, by which indeed no consistent results can be obtained. In ascertaining complementary colours it is absolutely necessary that a comparison white light of known composition be used. Without this there is only a mental estimation of the white, in other words guesswork.

Light and Colour.

By Dr. R. A. Houstoun. Pp. xi + 179 + 10 plates. (London: Longmans, Green and Co., 1923.) 7s. 6d. net.