36 A PHILOSOPHER WITH NATURE 



be attended to who could resist it ? But a para- 

 site withal ; outside human society the most dis- 

 tinguished and accomplished parasite in life. 



The black swifts screaming loudly and hawking 

 for insects overhead move slowly across the sky to 

 the west. As the light wanes in the late afternoon 

 an effect that must have some deep bearing on the 

 migration of birds is noticeable in this landscape 

 where the ground is always black. In the west the 

 sun floods the sky, the golden light shining through 

 the transparent wings of the flying insects, and 

 through the tops of the birches where more than one 

 song-thrush is now pouring forth its evening melody. 

 But all the east is sombre. The shadows fall 

 towards it, long, dark and gloomy, and with a 

 depressing effect which is like a leaden weight on 

 the senses and emotions. It is remarkable in the 

 psychology of wild life as in the psychology of peoples 

 how insufficiently we have taken account of the 

 deep-reaching, soul-seizing effects of waning light 

 which is falling away from us. 



It is one of the facts in the migrations of birds 

 over which naturalists have always found a difficulty 

 that the migrants both in the eastern and western 

 hemispheres should in their journey to the south 

 often begin to leave their haunts before the food 

 supply in any way fails them, and before they have 

 any physical want known to us indicating a coming 

 change in the conditions of life. But students of 

 the subject have probably not fully reckoned with 

 the deep emotional effect on all wild nature of the 

 waning light in the declining year, and on the 

 uncontrollable instinct to follow the sinking sun 

 begotten in those whose habits of life it affects. 



