Speaking of such imitations, we may note that fakers contemporary with the artist are perhaps the most dangerous to the neophyte, and as imitations have always existed more or less, and are by no means only the product of the greed of modern fakers and dealers, a collector is often taken in by a false Corot or a false Rousseau, in which the only legitimate thing is perhaps the date, the forgery having been perpetrated during the master’s lifetime. Naturally, the imitation is not always made for the purpose of cheating, but almost always with the hope of becoming as popular as a certain master by imitating his style. It is very often the work of pupils, as in the case of the Watteau imitations by Lancret and Pater. It is known that the work of Paul Potter has been imitated by Klomp, that Jacob van Huysum has counterfeited the work of Breughel and of Wouwermans, that Constantin Netscher made plenty of money copying Vandyke Charles I portraits, and that Teniers the Younger sold false Titians. To go back to prints and etchings before closing this chapter one must make a distinction between old imitations and modern ones. A good connoisseur is never at a loss to detect signs of counterfeit, but there is an essential difference of criterion needed in judging old imitations of etchings and modern imitations. In old prints involuntary discrepancies are sure to occur as they have been reproduced by hand, and the connoisseur must therefore be acquainted with them. These variations are more or less known to experts, whereas in the case of a modern purely mechanical reproduction, a magnifying glass and technical experience are the chief requirements. Marco Dente’s reproduction of Marcantonio’s work and the copies of Callot’s etchings by some of his pupils are examples of the imperfections of old imitations, details having been omitted. CHAPTER XX FAKED SCULPTURE, BAS-RELIEFS AND BRONZES Faked sculpture--Clay work--The false Tanagras--Imitation of Renaissance work--Bas-reliefs and busts--Baked clay and _stucco-duro_--The Clodions--Bronzes--The importance of patina--The patina of Pompeiian bronzes and excavated bronzes --Renaissance patina and that of later times--Gilded bronzes --Marble work and its general colouring--Sculpture in wood and ivory--The Ceroplastica.