Bruxelles, Photographie Instantanée E. Verhassels, 4 Chaussée de Gand Bruxelles, 1891, Albumen print, approximately 17,5 x 24 cm or 6.9 x 9.5 inches, with the photograph imprint on the mount stuck on a board (trace of a waterstain on the lower part), under glass and wood frame.
The Secretage is a process in which mercury, or some of its salts, is employed to impart the property of felting to certain kinds of furs. This process introduced around 1727 in Paris by named Dubois, companion hatter The workmen who carried out this operation after a few years was reached by an intoxication of this metal. The accidents which appear to depend of secretage are the tremor of the teeth, of the arms, often of all the body. TENON, Instit. Mém. scienc. 1806, 1er sem. p. 101 - 107


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