428 
Dr. G. Bakker on the 
point P in fig. 2 or fig. 6 ; while in the case that the 
capillary layer is enveloped by the liquid, the minimum value 
of the pressure p t in the liquid is given by the point G in 
figs. 2 and 6. We get, therefore, for the complete set 
of pi—w-curves the curves of fig. 7. The curve A x Ci cor- 
responds to a vapour-bubble, for which the pressure in the 
VoIzitt -axis 
liquid, round about it, has a minimum value. The corre- 
sponding radius of the spherical vapour-bubble is given by 
the formula: 
R r = - 
*y 
2H' 
(21) 
V 2 + V 2 ' — («i+ Vi) px — J? m in. ' 
where pwn.=pi corresponds to the point Aj. Because the 
total departure of the law of Pascal has not necessarily 
reached already its maximum value, I have written H' instead 
of H, H presenting the maximum value of the surface- 
tension*. In the following manner we may show that 
nevertheless W is of the same order of greatness as H. For 
the temperature T=0*844 T k I have found f that the thickness 
* When, namely, the radius of the spherical vapour-bubble has a value 
of the same order as the sphere of action, or smaller, the surface-ten$io?i 
is a function of the radius. 
t Zeitschr.f phys. Chetn. li. pp. 358 & 361 (1905). In the Phil. Mag. 
for October 1907, p. 522, I have driven for a temperature T = 0'82Ta : 
, _ surface-tension 
vapour-press me ' 
