A new method'of forming very fine wires by an elec trolytic treatment has been recently brought out at Paris by H. Abraham, a well-known physicist. The process consists in diminishing the section of a wire by using it as a soluble anode in an electrolytic cell. The resistance of the wire is taken at intervals and this gives an idea of the rate at which the section is diminished. The action is thus controlled and the current is cut off when the proper point has been reached. However, in order to obtain a regular section of the wire by this process, we must observe certain precautions. In the first place, the bath must be very dilute and have a high resistance so as to give a uniform distribution of current over all the length of the wire. This also allows some latitude in placing the two electrodes and they need not be given an exactly defined position. The best solution seems to be distilled water containing a few thousandths by weight of copper sulphate, or for silver wires, nitrate of silver can be used. Second, the operation should be carried out very slowly, so that the salt which forms around the wire will have time to diffuse in the bath. If this point is not observed the bath becomes conducting to great extent when the current is high and the wire is broken. The current density to be used here is on the order of 0.01 ampere per square centimeter surface of the wire. It is well to cut down the current density as the section of the wire diminishes. The experiment can be made very conveniently in a porcelain dish such as is used in photography. Here the wire can be seen readily. It is suspended by the ends from glass hooks and is soldered at the ends to two metal rods which lie outside the bath so as to avoid local circuits. "Electrical Review."