Some unclassified mechanical properties of solids and liquids

Abstract

In ordinary physical investigations solids and liquids are treated as having density and two species of elasticity. The limits of elasticity are also recognised as regards direct pull or thrust and shear; and since fracture or yielding of solids under these stresses give a convenient measure of their strength for constructional purposes this subject has received much attention.In liquids and semi-liquids the resistance to shear is known as viscosity, and is taken to be directly proportional to the rate of shearing. If the forces of surface attraction are included, the above-mentioned list contains all the qualities (not chemical or electrical) from which the behaviour of the materials in various circumstances is generally deduced.In conversation and ordinary language, however, many other qualities are definitely recognised and have been distinguished by special adjectives, but their relations to the fundamental properties of the substances which exhibit them are unclassified. A list of some of these adjectives is subjoined, and it is the purpose of the present note to suggest the relations between the qualities so denoted and the various measurable constants of the substances to which they are applicable.