CHAPTER XII 



PHOTOGRAPHIC RESEARCHES AND PORTRAITURE 



"\VhHt«'ver he touchwi he was Hure to draw from it soinethiriK that it had never l)efore 

 yieliltfi, and he was wholly frix- from llial familiurity which comes to tlie professed »ludent in 

 every branch of science, and l)lin<ls the metital eye to the si;,'ni(icance of tilings which are over- 

 l<x)k«l iKicaiis*! always in view." Nature on Chaklbb Darwin, V()1. xxvi, p. 147. 



We have seen in the preceding chapter how Galton supposed composite 

 portraiture to be connected fundamentally with psychological inquiry. 

 Galton developed comixjsite photography in his search for a method of 

 ascertaining wnether physiognomy Ts an index to mind, i.e. whether facial 

 chai-acteristics are correlated with mental traits. The actual method he 

 employed, however, was curiously enough suggested to him as a result of his 

 attempts to illustrate the multiple geographical features of a country, where 

 he wanted more than could be reiiddy exhibited on the usual type of maps. 

 Galton's own idea of composite portraiture would fully justify our discussing 

 it under the heading of " Psychometric Investigations." But as Galton's 

 contributions to scientific photography are numerous and important, it haa 

 seemed to me desirable to devote an entire chapter to the subject, although 

 much that will be contained in this chapter has great psychometric interest. 

 Galton's contributions to photographic science break up into six sections, 

 namely : 



{A) Composite Photography. 



{B) Bi-projections by Photography. 



iC) Analytical Photography. 



\D) Measurements by Photography. 



IeS Indexing and Numeralisation of Portraits. 



(F) Measurements of Resemblance, chiefly by photographs. 

 We shall also include in this chapter, as closely related to our present 

 topics, the subjects of the indexing of portraits and the telegraphy of portitiits. 

 The matters to be discussed occupied Galton's mind almost continuously 

 from 1878 to 1911, i.e. more than thirty years. They had singular fascination 

 for him not only because they combined fairly simple mathematical investi- 

 gation with mechanical invenjtion and experiment, but also because they 

 were closely associated with psychological and hereditary inquiries. 



{A) Composite Photography. 



There is a paper on combining various data in maps which explains the 

 origin of Galton's inquiries into composite photography. As ho hiinsolf say-^ 

 in a paper of 1878 : 



" It was while endeavouring to elicit the principal criminal types by methods of optical 



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