HOW NATURE STUDY SHOULD BE TAUGHT 133 



the blind, but you, who know not the delights of 

 a microscope, are suffering from exactly the same 

 misfortune, for you, too, are blind. You see that 

 tree and its foliage, but the microscopist sees the 

 structure of the mosses, lichens, and tiny algae 

 that ornament the trees. You exclaim over the 

 scarlet tanager that is flitting about in the top- 

 most branches. What a pleasure to you and 

 what a loss to the blind man ! But the microsco- 

 pist says, " I have seen the wonderful structure, 

 and learned the interesting habits of the aphides 

 and leaf miners," although his use of the micro- 

 scope may have been as unskillful as your use of 

 your unaided eyes. You have lost in relation to 

 him exactly the same in quality if not in quantity 

 as the blind man has lost in his relation to you. 

 Strange, is it not, that so many are microscopi- 

 cally blind ? and the pitiable phase of it is, that 

 the victims are ignorant of their loss. In this 

 sense, the use of high-power lenses and of showy 

 instruments is not a guarantee against micro- 

 scopical blindness. Sometimes " the heavens 

 open " in the infinitely near world after years 

 of microscopical skill. But that is another 

 matter. 



What I would especially impress upon teach- 



