NATURAL HISTORY STUDIES 



we call to our aid all sorts of devices for seeing more 

 clearly. " What is this," we say, "in itself and in 

 all its parts ? What is this by itself and when 

 compared with its fellows and kindred ? " and our 

 answer broadens and deepens till it furnishes the 

 raw materials of one quarter (the anatomy quarter) 

 of the whole science of Life-Lore or Biology. 



Close upon the first question, What is this ? 

 there rises a second How does this work ? The 

 two questions are equally natural and equally 

 necessary, and the science of living creatures makes 

 most progress when they are not far apart. They 

 prompt one another to more and more penetrating 

 inquisitiveness. The key-word of the one is structure 

 or make-up ; the key-word of the other is function 

 or activity. The creature that the first question 

 killed and picked to pieces has to be put together 

 again and made to work. What does it do ? How 

 does it do it ? How does it go ? How does it 

 keep agoing ? How long can it go ? How does 

 it cease from going ? In other words, how does the 

 living creature feel and move ? How does it grow 

 and multiply ? How does it waste, recover itself, 

 and finally, in most cases, die ? Above all, can we 

 find out anything about the secret of its activity 

 and of its power of answering back in a purpose- 

 like way to the changeful circumstances of its 

 everyday life ? These questions are all just different 

 forms of the question which that great genius, 

 Professor Clerk Maxwell, used to ask with much 

 persistence when he was a boy : " What is the go of 

 this the particular go of this ? " The answers 



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