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HOME-MADE TOYS FOR GIRLS AND BOYS
Fig. 205.—A Single Cell.
Figs. 206 and 207.—Details of Zinc and Carbon.
of one connected to the zinc of the other. Twisting the connecting wires into coils, as shown, is a good method of taking up the slack.
The Bi-chromate Battery Fluid is made up of bi-chromate of potash, sulphuric acid, and water, in the following proportions:
4 ounces of bi-chromate of potash
4 ounces of sulphuric acid
1 quart of water
in making up this solution, first add the acid to the water,—never add the water to the acid,—and then, when the solution is nearly cool, add the bi-chromate of potash. Pour the acid into the water slowly, because the combination of the two creates a great deal of heat, and if the heat
