387 
electrical and chemical changes. 
pile ; and that alkaline matter always appeared at the nega- 
tive, and acid at the positive pole:* and Dr. Henry about 
the same time made some unsuccessful attempts to decom- 
pose potassa in solution by the pile, and confirmed the general 
conclusions of MM. Nicholson, Carlisle and Cruickshank. 
In the month of September in this year, I published my first 
Paper on the subject of Galvanic Electricity, in Nicholson’s 
Journal, which was followed by six others :-f the last of 
which appeared in January, 1801. In these Papers I showed 
that oxygen and hydrogen were evolved from separate por- 
tions of water, though vegetable and even animal substances 
intervened ; and conceiving that all decompositions might be 
polar, J I electrised different compounds at the different ex- 
tremities, and found that sulphur and metallic substances 
appeared at the negative pole, and oxygen and azote at the 
positive pole, though the bodies furnishing them were sepa- 
rate from each other. In the same series of papers I esta- 
blished the intimate connexion between the electrical effects 
and the chemical changes going on in the pile, and drew the 
conclusion of the dependence of one upon the other. In 1802 
I proved that galvanic combinations might be formed from 
single metals, or charcoal and different fluids chiefly acid 
and alkaline, and that the side or pole of the conducting sub- 
stance in contact with the alkali was positive, and that in 
contact with the acid, negative ; and in the same year I pub- 
lished, that when two separate portions of water, connected 
by moist bladder or muscular fibre, were electrised, nitro- 
muriatic acid appeared at the positive, and fixed alkali at the 
negative pole.J In the same year Dr. Wollaston placed 
* Nicholson’s Journal, Vol. IV. p. 190. f Ibid, pp. 275, 326, 337, 394, 380. 
t Journal of the Royal Institution, 1802, First Series. 
