378 



SCIENCE. 



[Vol. V., No. 118. 



COMPOSITE PORTRAITS OF MEMBERS 

 OF THE NATIONAL ACADEMY OF 

 SCIENCES. 



Those of the members who were present at 

 the Washington meeting of the academy last 

 spring will remember, that, at the request of 

 Professor Brewer and myself, they sat for their 

 separate photographed portraits for the purpose 

 of obtaining an experimental composite picture. 

 Professor Baird kindly offered the facilities of 

 the photographic department ; and the pictures 

 taken by Mr. Smilie, the photographer in charge, 

 bear the same stamp of excellence that char- 

 acterizes so generally the work of that depart- 

 ment of the national museum. 



As onl} T one or two previous attempts, I 

 believe, have been made to produce composites 

 in this country, I will state briefly what they 

 are, and how they are made. 



The idea in its broadest sense was conceived 

 and applied by Francis Galton for the purpose 

 of obtaining an average or type . portrait ; 

 i.e., a picture that should show the features 

 that are common to a group of individuals, 

 and exclude those that are purely individual. 

 It is clear, that, in proportion as this result 

 is attainable, the method will be of value in 

 obtaining a clear conception of the external 

 characteristics of any given type or class. 



Galton reminds us, that, during the first days 

 of a traveller's meeting with a very different 

 race, he finds it impossible to distinguish one 

 from another, without making a special effort 

 to do so : to him the whole race looks alike, 

 excepting distinctions of age and sex. The 

 reason of this is, that, by short contacts with 

 man}- individuals, he receives upon his retina, 

 and has recorded upon his memory, a com- 

 posite picture emphasizing only what is com- 

 mon to the race, and omitting the individuali- 

 ties. This also explains the common fact that 

 resemblances among members of a family are 

 more patent to strangers than to the relatives. 



The individuals entering into these com- 

 posites were all photographed in the same 

 position. Two points were marked on the 

 ground glass of the camera ; and the instru- 

 ment was moved at each sitting to make the 

 eyes of the sitter exactly coincident with these 

 points. The composites were made by my 

 assistant, Mr. B. T. Putnam, who introduced 

 the negatives successive!}- into an apparatus 

 carefully constructed by himself, and essentially 

 like that designed by Mr. Galton, where they 

 were photographed by transmitted light. The 

 arrangements of the conditions of light, etc., 

 were such that an aggregate exposure of sixt} T - 



two seconds would be sufficient to take a good 

 picture. What was wanted, however, was not 

 an impression of one portrait on the plate, but 

 of all the thirty-one ; and to do this required 

 that the aggregate exposure of all the thirty- 

 one should be sixty-two seconds, or only two 

 seconds for each. Now, an exposure of two 

 seconds is, under the adopted conditions, too 

 short to produce a perceptible effect. It results 

 from this, that only those features or lines that 

 are common to all are perfectly given, and 

 that what is common to a small number is only 

 faintly given, while individualities are imper- 

 ceptible. The greater the ph\ T sical resem- 

 blances among the individuals, the better will 

 be the composites. A composite of a family 

 or of near relatives, where there is an under- 

 lying sameness of features, gives a very sharp 

 and individual-looking picture. 



It would be difficult to find thirty-one intel- 

 ligent men more diverse among themselves as 

 regards facial likeness than the academicians 

 entering into this composite. They are a group 

 selected as a t} T pe of the higher American intel- 

 ligence in the field of abstract science, all but 

 one or two being of American birth, and nearly 

 all being of American ancestry for several gen- 

 erations. The faces give to me an idea of per- 

 fect equilibrium, of marked intelligence, and, 

 what must be inseparable from the latter in a 

 scientific investigator, of imaginativeness. The 

 expression of absolute repose is doubtless due 

 to the complete neutrality of the portraits. 



Fig. 3 contains eighteen naturalists and thir- 

 teen mathematicians, whose average age is 

 about 52 years. Fig. 1 contains twelve mathe- 

 maticians, including both astronomers and 

 physicists, whose average age is about 51f 

 3'ears. Fig. 2 is a composite of sixteen natur- 

 alists, including seven biologists, three chem- 

 ists, and six geologists, with an average age 

 of about 52^- years. 



I ma} r mention, as perhaps only a remark- 

 able coincidence, that the positives of the 

 mathematicians, and also of the thirty-one aca- 

 demicians, suggested to me at once forcibly the 

 face of a member of the academy who belongs 

 to a family of mathematicians, but who hap- 

 pened not to be among the sitters for the com- 

 posite. In the prints this resemblance is less 

 strong, but in these it was observed quite in- 

 dependently by man} 7 members of the academy. 

 So, also, in the positive of the naturalists, the 

 face suggested, also quite independently to 

 myself and many others, was that of a very 

 eminent naturalist, deceased several years 

 before the sitting for this composite. 



There is given also a composite (fig. 4) of 



