engraved the name of COSTOU, 1745, without any Christian name: but, as there were two brothers of that name, Nicolas and Guillaume, natives of Lyons, and both excellent sculptors, it is become a matter of doubt by which of them these master-pieces were executed; though the one died in 1733, and the other in 1746. It is conjectured, however, that fraternal friendship induced them to share the fame arising from these capital productions, and that they worked at them in common till death left the survivor the task of finishing their joint labour. To whichever of the two the merit of the execution may be due, it is certain that the fiery, ungovernable spirit of the horses, as well as the exertion of vigour, and the triumph of strength in their conductors, is very happily expressed. The subject has frequently afforded a comparison to politicians. "These statues," say some observers, "appear to be the emblem of the French people, over whom it is necessary to keep a tight hand."--"It is to be apprehended," add others, "that the reins, which the conductors hold with so powerful an arm, are too weak to check these ungovernable animals." [Footnote 1: _De l'Etat de la France, à la fin de l'an VIII._ page 270.] [Footnote 2: Ibid. page 274.] LETTER XXX. _Paris, Dccemler 8, 1801_. You desire that I will favour you with a particular account of the means employed to transfer from pannel to canvas those celebrated pictures which I mentioned in my letter of the 13th ult°. Like many other, things that appear simple on being known, so is this process; but it is not, on that account, the less ingenious and difficult in execution. Such is the great disadvantage of the art of painting that, while other productions of genius may survive the revolution of ages, the creations of the pencil are intrusted to perishable wood or canvas. From the effect of heat, humidity, various exhalations to which they may be carelessly exposed, and even an unperceived neglect in the priming of the pannel or cloth, master-pieces are in danger of disappearing for ever. Happy, then, is it for the arts that this invaluable discovery has been lately brought to so great a degree of perfection, and that the restoration of several capital pictures having been confided to men no less skilful than enlightened, they have thus succeeded in rescuing them from approaching and inevitable destruction.