[63] Dr. Priestley among his other experiments on electricity first ascertained the conducting power of charcoal and the calcination and vitrification even of the most perfect metals by the electric spark. He seems first to have used large batteries, which M. Van Marum and his associates have carried to such extent. The solutions of the metals, the gasses produced and the circumstances which accelerate and prevent these effects in Galvanic processes with the pile of Volta, as detailed by Dr. Priestley in his paper on this subject in Nich. Journ. for March 1802 p. 198 form very important additions to the mass of knowledge respecting the Galvanic fluid. Nor are his discoveries in pneumatic electricity, of the conversion of oils, spirit of wine and the alkaline gass into inflammable air or hydrogen of less moment. [64] Dr. Bostock, who seems to have many requisites to qualify him as the historian of particular branches of science, has published a good attempt toward the history of Galvanism in Nicholson’s Journal. These histories of detached branches of Science, would not only be highly useful, but they may be considered as in some measure necessary to the accurate pursuit, and advancement of science itself. They are not only useful for the purpose of shewing the discoveries that have been made, and the time of their publication, the ideas that appear to have suggested them, the persons to whom we are indebted for them, and their effect on the spirit of enquiry at the time, but they prevent a man of science from being led into mistakes, from doing what has been already done, from suggesting what has been already published, and from ignorantly claiming to himself the merit due to the labours of a predecessor. Books are now so multiplied, in languages so various, obtained with so much difficulty, and at an expence so far exceeding the usual means of scientific men, that those who like Dr. Priestley fully and faithfully execute a work of this description are real benefactors to mankind.[65] [65] The transactions of the various academies and philosophical societies in Europe amount at least to 1000 volumes in quarto. The royal society of England in 1665 led the way to similar institutions.