SOME FUNDAMENTAL MISCONCEPTIONS 321 



foundations, and the pupil often comes to look at all living 

 things from a wrong angle. 



All living things work in intimate relationship with the 

 forces of the physical world. Life itself can do nothing 

 save as it draws energy from the lifeless. The life stuff of 

 plants and animals establishes relationships with sunlight 

 and the air, with laws of diffusion and evaporation, and 

 life depends upon taking advantage of these forces, upon 

 establishing these relationships. As skilful engineers have 

 harnessed water power, and steam, and electricity to do 

 their bidding, so the life stuff of plants and animals har- 

 nesses similar forces, till life itself is primarily a thing of 

 adjustment to external forces. It is these common rela- 

 tionships which we cannot afford to misunderstand if we 

 are to teach intelligently about plants and animals. 



It is evaporation which does the work of delivering to 

 the corn leaf the materials which, transformed, will fill the 

 swelling kernels. It is because the laws of diffusion must 

 be satisfied that materials are moved in the plant body, 

 and the plant is served by a system of transportation which 

 requires no expenditure of its own energy, a method which 

 in economy and efficiency excels the method of the throb- 

 bing heart. It is sunlight which runs the delicate and 

 mysterious food-making mechanism in the leaves. 



To study biology we must study physics and chemistry. 

 Nature study and elementary agriculture must include 

 •lessons exemplifying the operation of physical laws and 

 simple chemical reactions. There is a common core 

 which runs through the activities of all living things what- 

 ever their special forms and structures, and it is with this 

 common core, in so far as we know it, with the few proc- 



