An invention, finally deserving of mention, and extremely useful to painting, was made known during this last epoch by a Ferrarese, and afterwards brought to perfection by others. Antonio Contri, son of a Ferrarese lawyer, who, for domestic reasons, had long settled at Rome, and next at Paris, feeling a natural bias for design, practised it in both those cities; but first displayed greater excellence in embroidery than painting. Returning into Italy, and establishing himself at Cremona, he was instructed in landscape by Bassi, in which he was accustomed also to introduce flowers, the branch of painting in which he most distinguished himself. He also succeeded well in perspectives and in animals. His pictures, and those of his son Francesco, who pursued his style, remain at Cremona, Ferrara, and their vicinity; but it was his new discovery, just alluded to, which obtained a more wide circulation and repute. This is the method of removing from walls to canvass any picture without the least injury to its design or colouring. Various trials of it, during the space of a year, instructed him how to compose a sort of glue, or bitumen, which he spread over a canvass of equal size with the picture he wished to transfer to it. Having applied this to the painting, and beaten it firm with a mallet, he cut the plaister round it, and applied to the canvass a wooden frame well propped, in order that the work might take hold, and come off equal throughout. In a few days he cautiously removed the canvass from the wall, which brought with it the painting; and, having extended it on a smooth table, he applied to the back of it another canvass, varnished with a composition more adhesive than the former. He then placed over the work a quantity of sand, which should equally compress it in all its parts; and, after a week's space, he examined the two pieces of canvass, detached the first by means of warm water, and there then remained on the second the whole painting taken from the wall. He applied this method in different houses of Cremona, for Baruffaldi in Ferrara, and in Mantua for Prince d'Harmstadt, governor of the city; so as to enable him to send some heads, or other works of Giulio Romano, thus removed from the ducal palace, to the emperor. The secret composition of his glue Contri always concealed, but similar attempts were made about the same period in foreign countries. In the journal of Trevoux it is stated that Louis XV. caused the celebrated painting of St. Michael, by Raffaello, to be removed from its original canvass to a new one, a process which succeeded admirably, for on this last the chinks and creases disappeared which had greatly injured the former.[60] From this account I have been led to doubt whether Contri were really the inventor of this art, as asserted by Ferrarese writers. I say only doubted, since I am unable to judge the question with precision, for want of ascertaining the exact year in which he first applied the method