Crystallization of Metals hy Electricity. 277 



we doubt that such a reproductive process must eventuate in the 

 evolution of some kind of germ ? but what such may be it would 

 be idle to speculate. I desire only to put the observed fact upon 

 record, and to engage the efforts of our members in the elucidation 

 of that most recondite, though most interesting subject — the repro- 

 duction and distribution of our fresh-water Bhizopocla. 



VI. — Crystallization of Metals hy Electricity under the Microscojje. 

 By Philip Braham, Esq. 

 Plate CVII. 

 During some years of scientific investigation I have been in the 

 habit of submitting every ehgible experiment to microscopic 

 examination, and during an investigation concerning a metal tried 

 the effects of electricity on it in connection with an acid solution. 

 I was dehghted to find a brilliant crystallization start into hfe, but 

 shortly becoming dull. Following up that experiment by using 

 neutral salts, and terminals of the base, have succeeded in crystal- 

 Hzing gold, silver, copper, tin, zinc, and lead, and have every reason 

 to beheve I shall be able ere long to crystallize every other metal. 



The instrument used I give a sketch of, and the electrical 

 stage (a diminutive double discharger, which does excellently for 

 spectrum analysis in connection with an induction coil) and gal- 

 vanic battery, with fittings for varying the quantity and intensity 

 of the electric current. The sketch of the discharger shows the 

 manner in which it is fitted. The two short pillars A A are of ivory, 

 turned to a cup-shape on the top to fit the balls; the springs 

 B B keep the balls in their place, and are fastened to the side of 

 the ivory pillars by the binding screws C C, to which the wires 

 from the poles of the battery are connected ; the ends of the dis- 

 charger rods are split to receive the short wires of the metal under 

 electrolysis. 



The battery is similar in its construction to Smee's, but with 

 carbon plates instead of platinized silver, and excited with bichro- 

 mate of potash and sulphuric acid, it has the advantage of not 

 evolving fumes or acid spray. The wheel at the end D is provided 

 with a break E, to keep the plates at any required depth in the 

 solution. The spring clip G connects any number in the series of 

 six cells. The solutions of the salts should be as strong as possible, 

 without a tendency to crystallize. 



A drop of the liquid is placed on a microscopic slip, and the 

 ends of the wires fitted into the discharge rods [dipped into it, and 

 kept apart not more than a tenth of an inch, lowering the battery 

 into the solution, and carefully watching the terminal in connection 

 with the zinc pole : the instant action is observed clamp the wheel, 



X 2 



