Name of Cell.Capacity of Cell.Electromotive
force in Volts.
Resistance
in Ohms.
Daniell2 quarts1·0791
Daniell Gravity2 quarts1·07910
Leclanché1 pint1·601·13
Leclanché2 pints1·601·10
Leclanché3 pints1·600·87
Agglomerate1 pint1·550·70
Agglomerate2 pints1·550·60
Agglomerate3 pints1·550·50
Fuller1 quart1·800·50

From this it is evident that if we joined up the two plates of a Fuller cell with a short wire presenting no appreciable resistance, we should get a current of (1·80 divided by 0·50) 3·6 ampères along the wire; whereas if a gravity Daniell were employed the current flowing in the same wire would only be a little over 1/10 of an ampère, since 1·079/10 = 0·1079. But every wire, no matter how short or how thick, presents some resistance; so we must always take into account both the internal resistance (that of the battery itself) and the external resistance (that of the wires, etc., leading to the bells or indicators) in reckoning for any given current from any cell or cells.

[4] In mixing sulphuric acid with water, the acid should be added in a fine stream, with constant stirring, to the water, and not the water to the acid, lest the great heat evolved should cause the acid to be scattered about.

[5] Spirits of salt.

[6] Oil of vitriol.

[7] Aquafortis.

[8] Power to set up a current of electricity.

[9] Depolarizer is the technical name given to any body which, by absorbing the free hydrogen, removes the false polarity of the negative plate.