376 



SCIENCE. 



[Vol. VIII., No. 194 



becomes human with all the great distinctions of 

 that term. 



ANTHROPOMETRICAL TESTS. 



Since Mr. Francis Galton conducted his an- 

 thropometrical measurements at the International 

 health exhibition, increased attention has been 

 given to the measurement of physical character- 

 istics and of the senses. Mr. Galton has received 

 letters from Tokio, from Eome, from Paris, and 

 elsewhere, asking for the necessary apparatus for 

 establishing a laboratory where the important 

 measurements of the body and testing of the 

 senses can be made. 



The importance of such observations is well 

 undei-stood. It will enable us to determine ac- 

 curately racial characteristics, to mark the stages 

 of individual growth, to detect abnormalities of 

 development in time to check them, to lay the 

 foundation for a rational education of the senses 

 and the muscles. 



Mr. Galton has been devoting much time to the 

 jjreparation of instruments for measuring the 

 head and the delicacy of the senses ; and Mr. 

 Horace Darwin, of the Cambridge scientific 

 instrument co., has aided him in the work. The 

 last Journal of the Anthropological institute of 

 Great Britain contains a preliminary account of 

 some of their devices. 



As regards the size of the head, it is well known 

 that the caps of university students are larger 

 than those of the uneducated population. With 

 a convenient method of determining the size of 

 the head in various directions, one could find at 

 what age generally and individually the growth 

 of the brain comes to a standstill. The method 

 of taking the measurements is still a matter of 

 controversy. The maximum breadth can be got- 

 ten by a pair of calipers, with rough teeth, like 

 those of a comb, to penetrate the hair. The max- 

 imum length from the glabella (the central point 

 between the eyebrows) is also easy to measure. 

 The great difficulty is in getting the height of the 

 head. Mr. Darwin's instrument for this purpose 

 is inserted into the two ear-holes, and a slight 

 projection is caught by the inner edges of the 

 orbits : this determines the horizontal plane, and 

 measurements are taken to either side from it. 

 He will improve the instrument by having a band 

 attached, to be inserted under the chin, and thus 

 press the frame close against the orbit. 



For the color of the eyes and hau-, Mr. Galton 

 suggests, instead of printed shades, which are apt 

 to fade, small disks of colored glass for the eyes, 

 and spun threads of this glass for matching the 

 hair. 



The usual form of dynamometer for measuring 

 the force of one's grip is objectionable, because 

 the maximum clutch depends on the width and 

 convenience of the instrument at its widest point. 

 Mr. Darwin is making an instrument to avoid this 

 defect. 



With regard to sight, Mr. Galton admitted that 

 there was no good recognized way of measuring 

 the acuteness of vision, but thought the simple 

 method of getting the distance at which one can 

 tell in what corner of a white card a black dot is 

 to be found, as good as any. Mr, Brudenell 

 Carter, who has published some interesting views 

 on the relation of eyesight to civilization, ob- 

 jected to this method, and preferred the test of 

 distinguishing two closely adjoining dots. There 

 are many good methods of testing the color-sense ; 

 and Dr. Cattell's experiments at Leipzig, on the 

 time it takes to perceive the various colors, are of 

 interest here. He found that it requires 8 ten- 

 thousandths of a second to see orange, 10 to see 

 yellow, 12 to see blue, 13 to see red, 14 to see green, 

 23 to see violet. The exposure was made by an 

 arrangement similar to the instantaneous shutter 

 of a camera. Great individual differences in the 

 perception of various colors appeared, and a sim- 

 ple form of his apparatus might be useful for test- 

 ing the color- sense. 



With regard to sounds, we have almost no ex- 

 act methods of measuring. The susceptibility to 

 pitch can be readil}^ measured. 



Mr. Darwin also exhibited before the Anthro- 

 pological society an ingenious contrivance for 

 measuring one's reaction time, which works on 

 the principle of snapping a rod, and arresting it 

 in its fall as soon as possible after the sound is 

 heard. 



The subject is really one of the highest practical 

 importance, and physiological as well as mechani- 

 cal problems are involved. A physiologist with a 

 mechanical bent would certainly find here a fruit- 

 ful field. 



i 



THE STUDY OF THE SENSES. 



The great name of Helmholtz stands for the 

 union of the physical and biological sciences. The 

 late Professor Clifford speaks of him as " the 

 physiologist who learned physics for the sake of his 

 physiology, and mathematics for the sake of his 

 physics, and is now in the first rank of all three." 

 In his ' Physiological optics ' and his analysis of the 

 ' Sensations of tone,' he gave to the world two 

 classical works, as invaluable to the physicist as to 

 the psychologist and physiologist. The real great- 

 ness of these studies, the new engine that he em- 

 ployed, consisted in recognizing the dual nature 



