EDUCATIONAL VALUE OF PHOTOMICROGRAPHY. 155 



through the minds of such men as Newton, Kepler, Lyell, Huxley, Ohm, 

 Faraday, Joule, Helmholtz, Le Conte, Darwin and scores of their con- 

 temporaries. 



The beginning of the twentieth century finds the major part 

 of the civilized world bound to recognize the power of scien- 

 tific thought and investigation in its bearing upon the prosperity of 

 nations, and the equality of man. More and more attention is wisely 

 being given to methods of teaching in our primary and secondary schools 

 as well as to college and university work. Such attention is even now be- 

 ginning to manifest its results, as we note men having completed their 

 university training for the Doctor's degree under twenty- five years of 

 age. No doubt it may truly be said that such men are brilliant, or have 



Fig. 22. Palate of a Whelk, y 90 Di- Fig. 23. 



ajietees. Polarized Light. eters. 



Proboscis of Fly. x SO Diam- 



exceptional advantages or both combined for the result attained, yet the 

 fact remains that elementary knowledge gained from secondary instruc- 

 tion molds to a great extent the future of the individual. This phase 

 01 study is all the more important since it is beyond the control of the 

 pupil. Beyond his control, for though volumes may be written, and in- 

 structors may be at hand, the average student does not early in life ap- 

 preciate the necessity or value of application to study. 



Interest in a subject is the prime factor in its mastery, and the 

 method of presenting the subject will tend either to stimulate or allay 

 the interest of the pupil. 



The time devoted to the study of a subject in the secondary school is 

 frequently very limited, and the teacher may profitably consider the 

 needs of the pupils and seek to originate such methods as will accomplish 

 the most for the time allotted. One important saving of time in the class 

 room, both for elementary and advanced work along most scientific lines, 

 is the use of pictures in making certain points clearly understood, and 



