Scattering of light by solid substances

Abstract

The observations already published on scattering of light by gases and liquids naturally led on to an examination of the behaviour of solids in this respect. At the first trial it was found that glass scatters very freely, the scattered light being blue, and in many cases almost completely polarised. The observation is so easy that it must almost certainly have been made before, though I have not met with any mention of it. No special arrangements are necessary. If a narrow parallel beam, say 6 mm. diameter, from the condenser of an electric lantern, is allowed to traverse the interior of a block of glass, the scattered light along the track will be conspicuous. This is a ready method of demonstrating the scattering by small particles. Numerous specimens of plate glass and optical glass have been examined. These all show the scattering, though they differ among themselves in respect of intensity and completeness of polarisation. The depth and purity of the blue colour goes of course with the latter.