The general confirmation by experiment of Poisson's theoretical results created a tendency to regard his hypothetical magnetic fluids as having a real existence; but it was pointed out by W.
The results were substantially the same as those given by Poisson's theory, so far as the latter went, the principal additions including a fuller investigation of magnetic distribution, and the theory of magnetic induction in aeolotropic or crystalline substances.
Poisson's Funeral Oration (Conn.
(This solution may be verified in the same manner as Poisson's theorem, in which k=o.) We will now introduce the supposition that the force Z acts only within a small space of volume T, situated at (x, y, z), and for simplicity suppose that it is at the origin of co-ordinates that the rotations are to be estimated.
When the rod extends or contracts longitudinally it contracts or .(- -U P extends radially and in the ratio a, known as Poisson's ratio, which in metals is not far from 4.
From Poisson's equations Archibald Smith deduced the formulae given in the Admiralty Manual for Deviations of the Compass (1st ed., 1862), a work which has formed the basis of numerous other manuals since published in Great Britain and other countries.
A list of Poisson's works, drawn up by himself, is given at the end of Arago's biography.
So highly did he think of Poisson's memoir that he made a copy of it with his own hand, which was found among his papers after his death.
The result, however, of Poisson's investigation is practically equivalent to that already obtained by Laplace.