BIOLOGY IN ITS WIDER ASPECTS 1201 



some cases, to find their way back to their nests; or how it is that 

 many a plant and animal may pass into a state of suspended 

 animation, so thorough that the bod}^ is brittle, and yet survive; 

 or how instinctive behaviour was evolved; or how from a common 

 breeding-place in the far Atlantic the larvse of the American eel 

 move westwards and those of the European eel move eastwards, 

 each to the continent where its parents were nurtured. 



Poincare once remarked that if the earth had been beclouded and 

 the stars hidden, man would have remained much longer in intel- 

 lectual bewilderment, but from the contemplation of the heavens 

 he got his first ideas of orderly uniformities, helped, no doubt in 

 certain countries, by the regular sequence of the seasons. Can it be 

 said that the routine of life has forced other questions on Man, the 

 solution or partial solution of which has meant a new world ? Perhaps 

 there has been nothing in Natural History so epoch-making as 

 Newton's linkage of the falling apple to the distant moon in one 

 great law, but we must not forget that in Animate as well as in 

 non-living Nature Man has continually pushed the question: 

 "Whence?" and that this has led him to the concepts of develop- 

 ment and evolution. Perhaps it is not unfair to say that the laws of 

 the conservation of matter and energy in the physical universe have 

 their analogues in the world of life in the scientific concept of the 

 continuity of generations, to wit, heredity, and in Liebig's great 

 idea of the circulation of matter from one embodiment or incarnation 

 to another. The air and the soil-water are bound by sunbeams into 

 leaves and flowers ; all flesh is grass and all fish diatom ; and the dust 

 that was once enchanted in a living body may enter the endless cycle 

 once more, though a long circuit first be fetched. 



Except during the Dark Ages, that vicious parenthesis in man's 

 intellectual development, there has been in regard to the realm of 

 organisms, as well as in regard to the domain of things, a ceaseless 

 pushing of the question : How does this work? and it was a new world 

 when Lavoisier, helped by Priestley's discovery or re-discovery of 

 oxygen, placed the living mouse beside the lighted candle, and 

 showed that both were burning. That was the beginning of bio- 

 chemistry. Henceforth the emblem of the living organism became 

 the burning bush, always aflame yet not consumed. This again was 

 the discovery of a new world, still being explored with the question 

 How? as torch. 



Our point is that to a certain bent of mind, the realm of organisms 

 is full of marks of interrogation — brain-stretching problems; and 

 that the attempts to solve these have been of profound importance 

 in the intellectual development of mankind, and must continue to 

 be provocative. 



We have spoken of interesting pictures, of the beautiful, of the 

 dramatic, of big ideas, and of brain-stretching problems, but it is 



VOL. II HH 



