Recent work on the specific heat of chemical elements in the solid state has led to important conclusions with regard to the values of the atomic heat at constant volume. The curves showing the variation of atomic heat with temperature are all of the same form, and any given curve can be transformed into any other merely by altering the scale on which the temperature is plotted. This implies that the atomic heat C v is a function of the temperature T, dependent on a single parameter, the function being the same for different elements. Thus C v = F (Θ/T), where Θ is a certain temperature characteristic of the element in question. According to the quantum theory Θ = βv = hv/k , where v is the characteristic atomic frequency, h is Planck’s constant, 6·558 x 10 -27 , k is the gas constant for a single molecule, 1·372 x 10 -16 .