The time I have given is calculated for experiments made with one pair of the nitric acid battery; it is, however, by no means necessary that this be employed, as probably any other form of voltaic combination may be efficient. It would seem more advisable to employ a diaphragm battery, or one which produces a constant current, as otherwise the time cannot be accurately determined. It is very necessary that the silver of plates subjected to this process be homogeneous. Striæ, imperceptible in the original Daguerreotype, are instantly brought out by the action of the nascent anion; probably silver, formed by voltaic precipitation, would be found the most advantageous. I transmit with this paper some specimens of the prints of the etched plates, and of electrotypes taken from them; and in conclusion would call attention to the remarkable instance which these offer, of the effects of the imponderable upon the ponderable: thus, instead of a plate being inscribed, as "drawn by Landseer, and engraved by Cousins," it would be "drawn by Light, and engraved by Electricity!" * * * * * A valuable receipt, which every Daguerreian should have in his memory, has been suggested from the fact that one of our fraternity lost his hand by an accidental cut, caused while fitting a likeness in a locket, by the points of copper cutting the palm of his hand, in such a manner as to render amputation necessary. _White of eggs is the best antidote against the poison of copper._ * * * * * For the Daguerreian Journal. PAINTING--ITS ORIGIN AND HISTORY. BY WILLIAM WALCUTT. There is no doubt of painting being coeval with written language, or it may be said, that the simple representation of figures, on tablets prepared for the purpose, were the first means used by men to record particular events, actions, and so forth, and may therefore be dated back farther than any written language; and, indeed, may be considered the foundation from which it sprung, it being not improbable, because it is so natural, that the very first dwellers on the earth may have recorded their young history by means of representations of corporeal objects.