The object of this enquiry was to ascertain and compare the electrical resistances of various kinds of urine, both in states of health and of disease.

The measurements were made by means of a Wheatstone's bridge, with alternating currents, and a telephone according to Kohlrausch's method.

The fluids were held in a U-shaped electrolysis tube (a drawing of which accompanies this paper), of an internal diameter of about 1·55 centimetres, and containing a delicate thermometer. Two disc shaped platinum electrodes, each with a diameter of 1·4 c'm., were arranged so as just to rest upon the surfaces of the urine, with a very thin film of the fluid upon their upper surfaces.