LIGHT AND LIFE. 125 
air, while the women, kept shut up, have a pale-yellow 
complexion. Barrow asserts that the Mantchoo Tartars 
have grown whiter during their abode in China, Rémusat, 
Pallas, and Gutzlaff, speak of the Chinese women as re- 
markable for a European fairness. The Jewesses of Cairo 
or Syria, always hidden under veils or in their houses, have 
a pallid, dead color. In the yellow races of the Sumatra 
Sound and the Maldives, the women, always covered up, 
are pale like tallow. We know, too, that the Esquimaux 
bleach during their long winter. These phenomena, no 
doubt, are the results of several influences acting at once, 
and light does not play the sole part in them. Heat and 
other conditions of the medium probably have a share in 
these operations of color. Still, the peculiar and powerful 
effect of luminous radiation as a part of them is beyond 
dispute. 
The whole system of organic functions shares in the 
benefits of light. Darkness seems to favor the preponder- 
ance of the lymphatic system, a susceptibility to catarrh 
in the mucous membranes, flaccidity of the soft parts, 
swellings and distortions of the bony system, etc. Miners 
and workmen employed in ill-lighted shops are exposed to 
all these causes of physiological suffering. We may notice, 
with regard to this, that certain rays of the solar beam 
affect animals like darkness; among others, the orange 
light, which, according to Bert, hurts the development of 
batrachians. Now, if this light is injurious to animals, it 
is not so to plants, as we have seen. In exchange, green 
light, which is hurtful to vegetables, is extremely favorable 
to animals. There is a kind of opposition and balance, 
then, as respects luminous affinities, between the two great 
kingdoms of life. White light, as Dubrunfaut says, seems 
to split up under the influence of living beings into two 
complementary groups, a green group and an orange 
group, which exhibit in Nature antagonistic properties. It 
