The judicial examination to which the ambush in the Gorbeau house eventually gave rise, established the fact that a large sou piece, cut and worked in a peculiar fashion, was found in the garret, when the police made their descent on it. This sou piece was one of those marvels of industry, which are engendered by the patience of the galleys in the shadows and for the shadows, marvels which are nothing else than instruments of escape. These hideous and delicate products of wonderful art are to jewellers’ work what the metaphors of slang are to poetry. There are Benvenuto Cellinis in the galleys, just as there are Villons in language. The unhappy wretch who aspires to deliverance finds means sometimes without tools, sometimes with a common wooden-handled knife, to saw a sou into two thin plates, to hollow out these plates without affecting the coinage stamp, and to make a furrow on the edge of the sou in such a manner that the plates will adhere again. This can be screwed together and unscrewed at will; it is a box. In this box he hides a watch-spring, and this watch-spring, properly handled, cuts good-sized chains and bars of iron. The unfortunate convict is supposed to possess merely a sou; not at all, he possesses liberty.