Dr. A. W. Campbell, by way of illustrating the uses of formol, gave a microscopic demonstration of a series of specimens, normal and pathological, taken from various parts of the nervous system, and therewith proved that in formolhardened portions of nervous tissue it was possible to satisfactorily stain all the constituent elements of those tissues and likewise to clearly demonstrate almost all the pathological changes in them which are to be revealed by other previously discovered methods.