i88i.j 
The Organisation of Matter. 
193 
rapidly in a contracted space. In the liquid neither of these 
results can occur. The diameter of the circle of motion is 
governed by the relations of the rotating speed to the central 
energy, and cannot be changed by any exterior force. It 
resists pressure, therefore, with great vigour. While the 
particles of the liquid readily change places, the liquid as a 
whole refuses to yield to pressure, the centrifugal energy of 
its innumerable circles of motion not admitting of being 
packed into smaller spaces, as in the gas and the solid. It 
is the rigidly elastic phase of motion. 
There are certain relations existing between the three 
forms of matter which require to be now considered. Wc 
refer to what has been known as latent heat, the disappear- 
ance of heat energy when solids become liquids, or liquids 
become gases, and its reappearance in the reverse cases. 
This seeming disappearance and reappearance are a neces- 
sary result of the inter-relations of the three forms of 
matter. 
If we consider a molecule of a solid as coming into con- 
tact with a molecule of a liquid, at the same temperature, 
is it probable that they would have the same impact influence 
upon each other ? Suppose, for illustration, we should 
strike with a pointed hammer upon a mass of liquid of the 
same weight, stopping the blow at the instant that the point 
of the hammer meets the surface of the liquid. Evidently 
there will be a much greater disturbance in the liquid than 
in the solid. It is a simple question of resistances. All the 
material of the hammer resists on the one part, while only 
a small portion of the liquid resists on the other. Thus the 
slight vibration which runs through the substance of the 
solid is paralleled by a considerable disturbance of the sub- 
stance of the liquid. 
This illustration applies exactly to the contact of single 
molecules. Each molecule of the solid is held vigorously in 
place by the surrounding attractions. The molecule of the 
liquid is held more feebly in place. The whole substance of 
the solid aids vigorously in the resistance to impaCt, while a 
much slighter resistance exists in the liquid. Thus the solid 
molecule strikes the liquid with the force of a minute ham- 
mer with a molecular point, while the liquid molecule strikes 
back with little more than its individual force. Therefore 
every stroke of molecule on molecule has the real effeCt of a 
considerable number of solid molecules striking a much less 
number of liquid. How can this advantage in the solid be 
obviated ? Evidently if the liquid molecules is not sitffi- 
ciently aided in its resistance by its fellows, it must possess 
