A Novel Form of Thermo-Electric Battery
Transactions of the American Institute of Electrical Engineers
If further proof were needed of the verv high thermo-electric power of metals in contacts with electrolytes, a very striking and conclusive proof may be found in the following experiments. The apparatus consists of a fused mass of caustic potash or soda maintained at a teinperature of .50O' to 800°C. into which two conducting rods are inserted, both of the same metal and as nearly alike as possible in every respect except form. One of the rods, marked B in Figs. 1 and 2, is of cylindrical form.
... f cylindrical form. The other, marked A, is in the form of a cylinder having a deep recess cut or turned out near one end, leaving at the end a short cylindrical head attached to the rod by a very narrow stem. In order to obtain two pieces of metal having, as nearly as possible, the same molecular structure and chemical composition, a uniform rod of Bessemer steeliiich in diameter and two feet long, was cut in two equal parts. The severed ends which were originally together at the middle of the rod are turned sinooth and flat to forml the lower or contact ends of the rods, A and B, shown in Figs. 1 and 2. The head formed on the end of A i5 J inch long and the stem by which it is attached is half an inch long and 1 inch in diameter. The two rods thus prepared are held parallel to each other and about i inch apart in a wooden clamp with their ends in the same plane at right angles to their axes. The rods are now inserted in a vertical position to a depth of j inch into the fused caustic alkali. The surface of the fused alkali should come above the head of the rod, A, but not above the stein, as shown in Fig. 2 . The cup used in this experiment to 223