Slide Rule for Prediction of Physical Constants

Abstract

In the previous paper (this journal, 14, 270 (1950)) the author suggested a simple slide rule based on the general temperature relation of vapor pressure of liquids obtained. In the present, several slide rules are proposed for prediction of such relations as viscosity and surface tension of liquids vs temperature, viscosity and thermal conductivity of gases vs temperature, and critical temperature and critical pressure from normal boiling point. This slide rule can be constructed when the correlation between a physical constant, y, and a related variable, x, is expressed by a general equation, f2(y)=f1(x)+C, in which f1 and f2 are functions of dependent variables, x and y, respectively, and C is a constant depending on substances. If a pair of corresponding values (x0, y0) are given, C is eliminated, and any other correspondings of x and y are obtained. That is, if an only one point is available for a physical constant of a substance, all other values for that substance are obtainable at a glance with an accuracy satisfactory for engineering purposes.