254 Mr. T. Tate on certain peculiar Forms 
and suggested the dynamic action of the ether; but the state of 
mathematics in his day did not allow of investigating the conse- 
quences of the latter idea. In attempting to do this in the pre- 
sent advanced state of mathematics, I have only added, for that 
purpose, to the Newtonian hypotheses, an exact definition of the 
wether, and the supposition that the atoms are spherical. In the 
first instance I appled the hypotheses as a foundation for a 
theory of light, having long since seen that the theory which 
proposes to account for the phenomena of light by the oscillations 
of the diserete atoms of a medium having axes of elasticity, is 
contradicted by facts, and must therefore be abandoned. This 
charge [ have brought against it in an article on elliptically 
polarized light in the Philosophical Magazine for April 1859 
(p. 288); and it has found no defender. When this first appli- 
cation was made, I had no conception of any modes of applying 
the same hypotheses to explain the phenomena of gravity, elee- 
tricity, galvanism, and magnetism. If they are found to admit 
of applications so varied and extensive, the explanations are no 
longer personal, the hypotheses themselves explain, because they: 
ave true. The only advantage I pretend to possess in these re- 
searches is, the discovery of the true principles of the application 
of partial differential equations to determine the motion and 
pressure of an elastic fluid. But this kind of reasoning, though 
it is indispensable for the establishment of the truth of the 
general physical theory, may be tried on its own merits, quite 
independently of its applic: ition in that theory. For this reason 
I expressed the intention of carefully revising the proofs of the 
propositions in hydrodynamics which have been alre: ady enun- 
ciated in this Journal, and the results of which have been applied 
in the physical theory. But my occupations do not allow of 
entering on this task ant present. 
Cambridge Observatory, 
March 16, 1861, 
XL. On certain peculiar Forms of Capillary Action. 
By Tuomas Tarn, Lsg.* 
IQUIDS rise in small tubes by what is called capillary 
action, that is, by the cohesion of the particles of the 
liquid for one another, as well as by their adhesion to the sides 
of the tube. It has been ascertained ihat the height to which a 
liquid is-raised by capillary action varies inversely as the dia- 
meter of the tube. The chief object of this paper is to deter- 
mine, by direct experiment, the law of capillary resistance exerted 
* Communicated by the Author. 
