The addition of a very small amount of zinc to mercury causes the mercury to act as if it were zinc alone, arising perhaps from the amalgam having the effect of bringing the zinc to the surface.
Battery Connections.—There are three methods of connecting cells to form a battery; they may be connected:
1. In series; 2. In parallel; 3. In series multiple.
A series connection consists in joining the positive pole of one cell to the negative pole of the other, as shown in fig. 72; this adds the voltage of each cell.
Thus, connecting in series four cells of one and one-half volts each will give a total of six volts.
Fig. 73 illustrates a parallel or multiple connection; this is made by connecting the positive terminal of one cell with the positive terminal of another cell and the negative terminal of the first cell with the negative terminal of the second cell.
A paralleled or multiple connection adds the amperage of each cell; that is, the amperage of the battery will equal the sum of the amperage of each cell.