NATURAL HISTORY STUDIES 



exuberance of good spirits had the simple wood- 

 chopper port-rayed in Thoreau's Walden, that when 

 a thing amused him, " he sometimes tumbled down 

 and rolled on the ground with laughter." Perhaps 

 we have here an expression of primitive playfulness. 



When we see beautiful sights, or hear fine sounds, 

 or the like, pleasant messages have, of course, 

 travelled by our nerves into our brains. But they 

 do not, so to speak, stop there. They set agoing 

 other messages, which travel out to the heart, 

 which beats differently ; to the larynx, which 

 vibrates ; to the lungs even, and to other parts. 

 In short, internal muscular movements occur. 

 As the result of these, a third set of messages travel 

 in again to the brain ; and when the circle is com- 

 pleted, we are pleased. Perhaps in this way one 

 gets nearer an understanding of certain gambols 

 and of the vocal play the song of birds, in which 

 internal movements are associated with strong 

 emotions. In any case, there is reason to believe 

 in a deep and subtle connection between emotion 

 and motion. Literally, Wordsworth's heart leaped 

 up when he beheld a rainbow in the sky, and filled 

 with pleasure as he watched the dancing daffodils. 



The play -nature of animal movements is clearest 

 when there is something unusual about them. Thus 

 Alix relates that on one occasion, when botanizing 

 on the Alps, his dog ceased to follow him on the 

 gradual path, and seemed deliberately to choose a 

 long slope of frozen snow. There he lay down on 

 his back, folded his legs, and slid down like a 

 toboggan. At the foot he rose quietly, looked up to 



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