1606.  I had an apparatus made (fig. 142.) in which a is a plate of shell-lac, b a fine platina wire passing through it, and having only the section of the wire exposed above; c a ring of bibulous paper resting on the shell-lac, and d distilled water retained by the paper in its place, and just sufficient in quantity to cover the end of the wire b; another wire, e, touched a piece of tinfoil lying in the water, and was also connected with a discharging train; in this way it was easy, by rendering b either positive or negative, to send a current of electricity by its extremity into the fluid, and so away by the wire e.

1607.  On connecting b with the conductor of a powerful electrical machine, not the least disturbance of the level of the fluid over the end of the wire during the working of the machine could be observed; but at the same time there was not the smallest indication of electrical charge about the conductor of the machine, so complete was the discharge.  I conclude that the quantity of electricity passed in a given time had been too small, when compared with the conducting power of the fluid to produce the desired effect.

1608.  I then charged a large Leyden battery (291.), and discharged it through the wire b, interposing, however, a wet thread, two feet long, to prevent a spark in the water, and to reduce what would else have been a sudden violent discharge into one of more moderate character, enduring for a sensible length of time (334.).  I now did obtain a very brief elevation of the water over the end of the wire; and though a few minute bubbles of gas were at the same time formed there, so as to prevent me from asserting that the effect was unequivocally the same as that obtained by DAVY in the metals, yet, according to my best judgement, it was partly, and I believe principally, of that nature.

1609.  I employed a voltaic battery of 100 pair of four-inch plates for experiments of a similar nature with electrolytes.  In these cases the shell-lac was cupped, and the wire b 0.2 of an inch in diameter.  Sometimes I used a positive amalgamated zinc wire in contact with dilute sulphuric acid; at others, a negative copper wire in a solution of sulphate of copper; but, because of the evolution of gas, the precipitation of copper, &c., I was not able to obtain decided results.  It is but right to mention, that when I made use of mercury, endeavouring to repeat DAVY’s experiment, the battery of 100 pair was not sufficient to produce the elevations[A].

[A] In the experiments at the Royal Institution, Sir H. Davy used, I think, 500 or 600 pairs of plates.  Those at the London Institution were made with the apparatus of Mr. Pepys (consisting of an enormous single pair of plates), described in the Philosophical Transactions for 1832, p. 187.

1610.  The latter experiments (1609.) may therefore