94 
Proceedings of the Royal Society 
4. On Yortex Atoms. By Professor Sir William Thomson. 
After noticing Helmholtz’s admirable discovery of the law of 
vortex motion in a perfect liquid, that is, in a fluid perfectly 
destitute of viscosity (or fluid friction), the author said that this 
discovery inevitably suggests the idea that Helmholtz’s rings are 
the only true atoms. For the only pretext seeming to justify 
the monstrous assumption of infinitely strong and infinitely rigid 
pieces of matter, the existence of which is asserted as a probable 
hypothesis by some of the greatest modern chemists in their rashly- 
worded introductory statements, is that urged by Lucretius and 
adopted by Newton; that it seems necessary to account for the 
unalterable distinguishing qualities of different kinds of matter. 
But Helmholtz has proved an absolutely unalterable quality in the 
motion of any portion of a perfect liquid, in which the peculiar 
motion which he calls “ wirbel-bewegung” has been once created. 
Thus, any portion of a perfect liquid which has “ wirbel-bewegung” 
has one recommendation of Lucretius’ atoms — infinitely perennial 
specific quality. To generate or to destroy “ wirbel-bewegung” in 
a perfect fluid can only be an act of creative power. Lucretius’ 
atom does not explain any of the properties of matter without 
attributing them to the atom itself. Thus the “ clash of atoms,” 
as it has been well called, has been invoked by his modern followers 
to account for the elasticity of gases. Every other property of 
matter has similarly required an assumption of specific forces per- 
taining to the atom. It is as easy (and as improbable — not more 
so) to assume whatever specific forces may be required in any por- 
tion of matter which possesses the “ wirbel-bewegung,” as in a 
solid indivisible piece of matter, and hence the Lucretius atom has 
no prima facie advantage over the Helmholtz atom. A magnificent 
display of smoke-rings, which he recently had the pleasure of wit- 
nessing in Professor Tait’s lecture-room, diminished by one the 
number of assumptions required to explain the properties of matter, 
on the hypothesis that all bodies are composed of vortex atoms in 
a perfect homogeneous liquid. Two smoke-rings were frequently 
