Abstract

The years between 1660 and 1800 were important ones in the study of light. For most of the period the work, especially in this country, was largely dominated by the theories advanced by Newton; unfortunately the protagonists of these theories were much more rigid in their approach than was Newton himself. There was, in effect, almost a century of ‘rear-guard actions’ to maintain the corpuscular theory at all costs.Fortunately, the advance of geometrical optics and the design of optical instruments was not retarded to a very great degree by this partisan approach. The workers in these fields were not, as a rule, too involved in speculation, and worked largely empirically.Some of the modifications to the original corpuscular theory are interesting. Attempts were made to explain, with varying degrees of success, total internal reflection, dispersion, interference effects, diffraction and phosphorescence. Considerable speculation about the velocity of light occurred in connection with these topics. At the same time, wave theories never completely died out and, although they were not developed until the early part of the nineteenth century, their influence was felt even in this country