330 Kreider — Experiments in Elementary Physics. 



bottle by a rubber stopper. The cell was held in proper posi- 

 tion by means of a clamp attached to the neck ot the bottle 

 and to the side of the lantern. 



A variety of readily changeable electrodes is provided by 

 the construction shown at C and D. The anode, C, is formed 

 of a No. 12 copper wire soldered to a rod of zinc ; the combi- 

 nation being bent into the form of an inverted U and attached 

 to the end of a brass rod about 3"" n in diameter. A similar 



Fig. 1. 



construction characterizes the cathode D ; in which a strip of 

 platinum, - 5 by 6 cm , and sufficiently stiff to be readily handled, 

 takes the place of the zinc of the anode. The brass rods of 

 these electrodes slide through the split brass bushings, H. The 

 latter are attached to one end of a brass rod, the other end of 

 which carries a binding post, and are supported by the lantern 

 rods, L, by means of iron rods and the ebonite insulators, E. 



It will be seen that by simply raising C or D sufficiently to 

 clear the sides of the cell and then rotating them through 180°, 

 a change of either electrode is promptly effected without any 

 disturbance of the electrical connections. 



