He then placed a series of pointed
pieces of paper, each separate piece being composed of two halves,
one of litmus and the other of turmeric paper, and all moistened
with sulphate of soda, in the line of the current from the machine.
The pieces of paper were separated from each other by spaces of air.
The machine was turned; and it was always found that at the point
where the electricity entered the paper, litmus was reddened, and at
the point where it quitted the paper, turmeric was browned. 'Here,'
he urges, 'the poles are entirely abandoned, but we have still
electrochemical decomposition.' It is evident to him that instead of
being attracted by the poles, the bodies separated are ejected by
the current. The effects thus obtained with poles of air he also
succeeded in obtaining with poles of water. The advance in
Faraday's own ideas made at this time is indicated by the word
'ejected.' He afterwards reiterates this view: the evolved
substances are expelled from the decomposing body, and 'not drawn
out by an attraction.
Having abolished this idea of polar attraction, he proceeds to
enunciate and develop a theory of his own. He refers to Davy's
celebrated Bakerian Lecture, given in 1806, which he says 'is almost
entirely occupied in the consideration of electrochemical
decompositions.' The facts recorded in that lecture Faraday regards
as of the utmost value. But 'the mode of action by which the
effects take place is stated very generally; so generally, indeed,
that probably a dozen precise schemes of electrochemical action
might be drawn up, differing essentially from each other, yet all
agreeing with the statement there given.
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