
"The corpse, being supposed at the bottom of the river, will there remain until, by some means, its specific gravity again becomes less than that of the bulk of water which it displaces. This effect is brought about by decomposition, or otherwise. The result of decomposition is the generation of gas, distending the cellular tissues and all the cavities, and giving the puffed appearance which is to horrible. When this distension has so far progressed that the bulk of the corpse is materially increased without a corresponding increase of mass or weight, its specific gravity becomes less than that of the water displaced, and it forthwith makes its appearance at the surface. But decomposition is modified by innumerable circumstances—is hastened or retarded by innumerable agencies; for example, by the heat or cold of the season, by the mineral impregnation or purity of the water, by its depth or shallowness, by its currency or stagnation, by the temperament of the body, by its infection or freedom from disease before death.
