PHYSICS: F. G. KEYES 
323 
To determine the effect of temperature, the behavior of zinc, glass, 
ebonite, pitch and wax was studied. The results, together with the 
preceding may be summarized in the following formulae:* 
S = A1 + A2T2 + AS Tz, 
A2 = C2 Fe^'^, C2 = E2 e^'\ 
A, = Cs P^'^'y Cz = Esd{T- e)-\ 
T2 = 1 - e-«vr, h = b e, 
'■• = (' + t-)'-&>)'' = '.+ -77Ef' 
5 = displacement (twist), P = applied torque, 
/ = time, to = duration of previous stress, 
6 = temperature, T = melting point, 
h, k, a, jE, Po, d, b, m, TT, constants. 
* Instead of this series coupling, the following may be substituted: The unit consists of 
four elements: (1), (2) and (3) are in viscous contact with (4). (1) and (2) are in elastic 
coupling; and finally (3) of this unit is connected with (1) of the next following unit by an 
elastic coupling. The resulting formulae, however, are not essentially different from those 
here given. 
A NEW EQUATION OF CONTINUITY 
By Frederick G. Keyes 
RESEARCH LABORATORY OF PHYSICAL CHEMISTRY. MASSACHUSETTS INSTITUTE OF 
TECHNOLOGY 
Communicated by A. A. Noyes, February 28, 1917 
This paper presents a pressure, volume, temperature relation which 
has been carefully compared with the greater part of the available ex- 
perimental data during the past ten years. The equation, valid when 
only one type of molecule is present, is 
^ r-— V (1) 
where log 6 = log — a/2;, and a, a, and h are constants; R is the 
universal gas constant. 
The equation is based on considerations resulting from the inferences 
regarding atomic structure, obtained since the discovery of the negative 
electron. The model atom consists of a positive central portion about 
