520 POPULAR SCIENCE MONTHLY. 



on the nervous system. From time to time experiments have been 

 made as to the influence of various colored lights, chiefly on the insane, 

 as first suggested by Father Secchi in 1895. Even yet, however, the 

 specific mental influences of the various colors are not quite clear. It 

 has been found by some that the red rays are far more soothing and 

 comfortable, less irritating, than the total rays of uncolored light, and 

 Garbini found that angry infants were soothed by the light through red 

 glass, only slightly by that through green and not at all by other 

 colored light. On the other hand, it is stated that a well-known dry 

 plate manufacturer at Lyons was obliged to substitute green-colored 

 glass in the windows of his large room for the usual red because the 

 work people sang and gesticulated all day and the men made love to 

 the women, while under the influence of green glass (which also allows 

 yellow rays to pass) they became quiet and silent and seemed less 

 fatigued when they left off work. We need not attach much value to 

 these statements, but in this connection it is interesting to refer to 

 the results obtained some years ago by Fere and recorded in his 'Sensa- 

 tion et Mouvement.' Experimenting on normal subjects as well as on 

 nervous subjects, who were found more sensitive, with colored light 

 passed through glass or sheets of gelatine, he found notable differences 

 in muscular power, measured by the dynamometer, and in the circula- 

 tion as measured by plethysmography tracings of the forearm under 

 the influence of different colors. He found in this manner with one 

 subject whose normal muscular power was represented by 23 that blue 

 light increased his power to 24, green to 28, yellow to 30, orange to 35 

 and red to 42. The dynamogenic powers of the different colors were thus 

 found to rank in the spectral order, red representing the climax of 

 energy, or, as Fere puts it, "the intensity of the visual sensation varies 

 as the vibrations." Fere found that colors need not be perceived in 

 order to show their influence, thus proving the purely physical 

 nature of that influence, for in a subject who was unable to see 

 colors with one eye, the color stimulus had the same dynamogenic effect 

 whether applied to the seeing or the defective eye. Increase of volume 

 of blood in the limbs, measured by the plethysmograph, so far as we 

 can rely on Fere's experiments, ran parallel with the influence on mus- 

 cular power, culminating with red, so that no metaphor is involved, 

 Fere remarks, when we speak of red as a 'warm' color. On the insane 

 the results attained by tbe use of colored glass do not seem to be quite 

 coherent. Some of the earlier observers described the beneficial effects 

 of blue glass in soothing maniacs. Pritchard Davies, however, was not 

 able to find that red light had any beneficial effect, though on some 

 cases blue had, while Roffegean found that, in the case of a somber and 

 taciturn maniac who could rarely be persuaded to eat, three hours in a 

 red-lighted room produced a markedly beneficial effect, and a man with 



