Concessions to Mr. Ivory. 365 
nearer to Mr. Ivory’s own, than that of Laplace, which he says 
has been “ sneered at”’ in the article Conxston. The author 
of that article does indeed observe, that Mr. Laplace has had re- 
course to ‘* the awkward contrivance of building up a curve, like 
the arch of a bridge, with fourteen blocks on each side:” the 
same contrivance having been originally employed in this coun- 
try, and then abandoned for the series: and Mr. Ivory’s own 
table appears fully to justify this abandonment: nor is it easy to 
conceive why he persists in dragging forwards the most illustrious 
of the French mathematicians into a comparison, which, with 
respect to the present investigation, cannot but be highly disad- 
vantageous to him. 
If, indeed, the truih is to be told, Mr. Laplace’s whole phy- 
sical theory of capillary action is rendered NUGATORY and DELU- 
stvE, by the omission of exactly one half of the conditions of 
the problem. He has attempted to deduce the laws of the equili- 
brium of two forces from the determination of the magnitude of 
one of them only. For it is most manifest and undeniable, that 
no substance, subjected to the operation of an attractive force, 
can remain at rest, without having that attraction counteracted 
by an equal repulsive force: and it is equally obvious that, in all 
common cases, the general amount of attraction and repulsion, 
reduced to any given direction, with regard to any given atom, 
must be equal. If therefore we suppose the joint or remaining 
force, depending on the mutual actions of two particles only, to be 
represented by a certain function of their distance, it is obvious 
that this function must be such as to afford a sum or integral, 
for all the particles within the sphere of corpuscular action, =0. 
And this is the true reason why Mr. Laplace’s earliest computa- 
tions have been silently abandoned, as affording no practical re- 
sult; and why they never can be resumed, even by those whom 
they have dazzled and astonished. I am, Sir, 
your very obedient servant, 
London, 3 Nov. 1821. S. B. L. 
Posrscriet. Though I am perfectly disposed to remain at 
peace with Mr. Ivory, 1 am obliged to add some furtker condi- 
tions to my capitulation ; since he does not appear to have ad- 
verted to my last postscript : otherwise he could scarcely have re- 
marked that I admit the number ‘00418, and that I ought to 
have said 00419. ‘This assertion brings the discussion within 
very narrow limits: I have chosen the case in which the two 
methods appeared to differ the most widely, and which is one of 
the most unfavourable to the convergence of the series: and one 
case is as good for the present purpose as a thousand. The 
difference of the results is only +45th of the whole quantity, and 
its 
