First edition, second issue. It was reissued in 1873 with “Ten Thousand” added on the title-page. With this book Darwin founded the study of ethology (animal behaviour) and conveyance of information (communication theory) and made a major contribution to psychology. A new era of animal psychology started with Darwin’s Expression and to this day it remains by far the most important single contribution to its subject. Darwin’s Expression is also one of the first books illustrated with collotypes. Besides the twenty-one woodcut figures the book is illustrated with thirty figures reproduced from photographs on seven heliotype plates. Some of the photographs were borrowed from Duchenne de Boulogne, the founder of electrotherapy, who in 1862 published his extensive experiments on producing ’artificial’ expression of emotions by electrical stimulation of the facial muscles in an album of 72 mounted photographs. Twenty-eight of the photographs were taken by the Swedish-born photographer Oscar Rejlander, who posed for many of them himself (and also his wife). Darwin tells in a letter that “I am now rich in photographs for I have found a photographer in London, Rejlander, who for years has had a passion for photographing all sorts of chance expressions exhibited on various occasions, especially of children, and taken instantaneously”. Darwin’s ’discovery’ of Oscar Rejlander added a new dimension to his study. Collation: Pp vi, 374 and 4 pp of advertisements, dated November, 1872. With 7 heliotype plates of which three are folding (plates numbered in Arabic), and 21 wood-engravings in the text. Publisher’s green cloth. Binding: Inner hinge cracked. References: Garrison-Morton 4975; Freeman 1142 (2nd ed., 1977); Boring, The History of Experimental Psychology, 233, 462-63; Gilman, Seeing the Insane, 179-87; Chancellor, Charles Darwin, 128; DSB, III, 575; The Truthful Lens 43 and pp 39-40; Norman 600; Hagelin KIB, 178-79. Waller 2298.