762 THE POPULAR SCIENCE MONTHLY. 



the drawings used in the art schools for the same purpose ap- 

 pear antiquated. Since then the English anthropologist, Mr. 

 Francis Galton, has solved by photography a problem which was 

 as much beyond the reach of the artist as the representation of 

 the average expression of a person was of the photographer — 

 namely, of collecting into a typical picture the average physiog- 

 nomy and shape of the head of a considerable number of persons 

 of the same age, race, like degree of mental development, or simi- 

 lar pathological condition or criminal propensity. This is done 

 by causing faint pictures of faces of the same category to cover 

 one another on the same negative.* Prof. Bowditch, of the Har- 

 vard Medical School, has in this way taken average (composite) 

 pictures or the types of American students and girl students, 

 drivers and conductors of horse-cars. In the last cases the supe- 

 riority of the intellectual exjDression of the conductor type over 

 that of the driver type is very plain. It would have been some- 

 thing for Lavater and Gall. 



Again, pathology comes into the service of fine art. Dr. Char- 

 cot has recognized, in the photographically fixed convulsive atti- 

 tudes and distortions of hysterics, the classical representations of 

 possessed persons, f It is indeed most wonderful to see how 

 Raphael, otherwise dwelling only in the ideal, portrayed in his 

 Transfiguration the figure of the possessed boy so realistically 

 that one can with certainty, from the Magendian position of his 

 eyes, diagnosticate a central disease. It is in harmony with this, 

 as was recently remarked in New York, that his left hand is af- 

 flicted with an athetoid cramp. J 



[To he concluded.'] 



Experiments by Herr Regel with reference to the influence of external factors 

 on the odor of plants show that the most important is the indirect influence of 

 light on the formation of etheric oils and their evaporation. Heat and light in- 

 tensify the fragrance of strongly fragrant flowers, which in darkness is lessened 

 without quite disappearing. "When the whole plant was darkened, those buds 

 only which were before fairly well developed yielded fragrant flowers, the others 

 were scentless. If, however, only the flowers were darkened, all were fragrant. 

 Other plants open their flowers and are fragrant only by night. When these plants 

 were kept continuously in the dark, they lost their scent, as they lost their starch. 

 When brought into light again, both starch and fragrance returned. Besides 

 light, respiration has a decided influence on the fragrance. In general, the open- 

 ing of flowers coincides with their fragrance, but there is no necessary connection 

 between these phenomena. 



* Inquiries into Human Faculty and its Development, with Illustrations. London, 1883. 

 f Compare Exner, a. a. 0. S. 21 et scq. 



\ Sachs and Peterson, A Study of Cerebral Palsies, etc. Journal of Nervous and Men- 

 tal Disease, May, 1890. 



