1904 - 5 .] Mr J. Fraser on Electricity based on Bubble Atom. 689 
so that the average state would be neutral. This property of atoms 
I propose to call elastic absorption. If the particles of the vibrating 
atoms lost position, or potential energy, so much would he sent 
away into space as a wave of heat, for the ether would rush in 
and occupy the space vacated by the crushed-in particles, and so 
would be energised to this extent, the heat sent into space re- 
presenting the potential energy lost, the remainder of the vibration 
restoring the pressure withdrawn during the inward phase. Thus 
no matter what the electricity of the atoms, provided their vibra- 
tions were proportionate to it, they would always be neutral. 
(The clause in italics will be understood later on.) 
On the other hand, if the temperature of an electrified body 
were kept constant, and it were perfectly insulated in an air 
vacuum, it seems to me that it ought to retain its electrification 
indefinitely. For only by a quickening of its rate or amplitude 
of vibration could it radiate away as heat any surplus electricity 
it might possess, or retain as electricity from heat supplied any 
deficiency of the same. 
10. And now, can we not gain a glimpse of the reason why 
gases liquefy at such enormously different temperatures? Some 
of the metals, for instance, liquefy at almost the highest tempera- 
ture attainable by artificial means, whilst the so-called “ permanent 
gases ” do not liquefy till almost the zero temperature is reached. 
It appears to me that the solution of the enigma lies in the 
elasticity possessed by the atoms, those substances possessing the 
greatest atomic elasticity (and, it might be, the smallest mass) being 
the last to liquefy.* It appears that when gases are near their point 
of liquefaction equal volumes of them no longer contain the same 
number of molecules as other gases at the same temperature which 
are further removed from this point. They cannot, owing to 
their lack of elasticity, keep the same space clear for themselves , 
and so are compelled by the external pressure to crowd closer 
and closer together till they liquefy. The metals, owing to their 
generally great mass, possess a goodly quantity of electricity 
* “ If fj. represent the mass of a particle in an atom of radius r, while there 
are n such particles per unit area of the surface, the external pressure p is 
balanced when nuv 2 =pr. That is when Mv 2 — SpY, where M is the mass and 
Y the volume of the atom.” 
PROC. ROY. SOC. EDIN. — VOL. XXV. 
44 
