1833.] Attraction and Repulsion. 527 
Parr IT.—Division 2. 
The minute inquiry which I have endeavoured to pursue into the 
laws of repulsion, I trust has shewn, that this force cannot vary either 
in a less, or the same, inverse ratio of the distance as the attraction. 
That this inquiry has not hitherto been strictly pursued, by the 
ablest writers on chemical philosophy, is evident from the numerous, 
and even opposite doctrines, which have been laid down to explain the 
various states, and degrees of combination, in which bodies exist ; and 
also from numerous passages throughout their writings. Thus the 
following quotation from the great Lavoisier will shew at once, that 
(from want of a sufficient investigation) he reasoned as if the two 
opponent forces to each other, attraction, and the repulsion from heat, 
varied in the same ratio. 
‘** We have already seen,”’ observes this eminent writer, ‘‘ that the 
same body becomes solid or fluid, or aeriform, according to the quanti- 
ty of caloric, by which it is penetrated ; or more strictly, accordingly as 
the repulsive force exerted by the caloric, is equal to, stronger, or weak- 
er than, the attraction of the particles of the bodies it acts upon.” 
And again he writes: ‘‘ But if these two powers only existed, bodies 
would become liquid, at an indivisible degree of the thermometer, and 
would almost instantaneously pass, from the solid state of aggregation, 
to that of aeriform elasticity. Thus water, for instance, at the very 
instant when it ceases to be ice, would begin to boil, and would be 
transformed into an aerifurm fluid, having its particles scattered indefi- 
nitely through the surrounding space*.” 
And in another place, he further states that, ‘‘ without the atmos- 
pheric pressure we should not have any proper aeriform fluids ; because, 
the moment the force of attraction is overcome by the repulsive power 
of the caloric, the particles of bodies would separate themselves inde-« 
finitely, having nothing to give limits to their expansion ; unless their 
own gravity might collect them together, so as to form an atmos- 
pheret.” 
It is only a want of due reflectiun on the laws of thetwo powers, 
that could have permitted the first of these passages to exist in the 
work of such an author. How could the attraction in a solid be great- 
er than the repulsion, without bringing the atoms together ? That they 
are not in contact, he himself has proved}. That the other statements 
* Elements of Chemistry, (translated by Kerr,) p. 55. 
+ Elenents, p. 56. 
~ Elements, p. 50. 
