"Life seems full of Ups and Downs" The explanation reads: "Each bed was originally provided with twelve loose boards fitted crosswise on the frame. Prisoners, however, were allowed only eight of these boards which supported a "palliasse" of wood shavings. Owing to the spaces of the boards, this mattress invariably developed uncomfortable humps and hollows. Later the palliasses were removed and prisoners had only boards on which to sleep."
This illustration is taken from "Handle With Care" by R. Anderson and D. Westmacott, a book of sketches made by Prisoners of War.