Trebel, George. [from old catalog] · New York, F. Tousey · leaf 31
purple will be changed to ared. Only acids turn purple cabbage infusion red. Now prepare a concentrated solution of sodium sulphate.Color the solution with a portion of the purple cabbage infu-sion, and partly flil the V-shaped glass tube (Fig . 4) withthis liquid. Employ a battery of two Grenet… … tube, a little distance apart, so that the current will beobliged to traverse a part of the liquid. Close the circuit;bubbles of gas are immediately disengaged from the platinumstrips; soon the liquid around the — pole is turned green,while that around the f pole is turned red. Evidently de- USE…
Electricity
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