William Thomson, Note on a Passage in Fourier's Heat
“ Now Fourier gives no demonstration of the possibility of this expansion, but he merely determines what the coefficients , , & would be, if the function were represented by a series of this form. Poisson arrives, by another method, at the same conclusion as Fourier, and then states this objection to Fourier’s solution; but, as is remarked by Mr Kelland (Theory of Heat, p. 81, note) , he “does not appear, as far as I can see, to get over the difficulty.” ”
