394 THE POPULAR SCIENCE MONTHLY. 



nize the difference between this precipitate and that other. Do 

 you think that you ever will be a chemist, sir ? An illusion, 

 sir, an illusion, a sad one ; waste of time and your father's money ; 

 better take a course in theology or judicial jurisprudence." Well, 

 many such an illustration may be real to-day also. It is true we 

 have gone a step further since ; we have now in most of the col- 

 leges that respect themselves physical laboratories, generally well 

 mounted ; here instruction is received and practice is obtained in 

 scales, dimensions, standard units, etc. But what would have 

 been a heaven for the twelve or thirteen years old boy becomes 

 only too often the place of torture for the nineteen, twenty, or 

 twenty-one years old young man ; unsuccessful in his attempts, 

 clumsy because not trained beforehand, he often wishes the whole 

 recitation to f orgetf ulness ; and a large number of students remain 

 afterward mere designers in technical offices or poor lecturers on 

 the so-called popular sciences, instead of following a successful 

 scientific career, doing original work, and possibly realizing dis- 

 coveries, imjDrovements, wealth, and honor. The many failures 

 here ought to serve as an emphatically practical lesson on the 

 necessity of adapting work to age. 



When the young man enters the laboratory at college, he 

 ought not to encounter any mechanical difficulties. His attention 

 ought to be chiefly directed to more abstract thoughts, to his 

 theories, his laws, etc. Expert with his fingers, his senses trained, 

 he ought to be able to note differences and similarities in the ex- 

 perimental phenomena, formulate his hypotheses about them, and 

 verify them. Very recently the writer had a good chance of see- 

 ing the above practically illustrated. The son of one of our lead- 

 ing citizens, entering his second year in Princeton, who had just 

 the training (tool-house work) recommended, was present at the 

 recitation in physics ; a fine apparatus was brought in and the 

 professor had some trouble in explaining to the class the working 

 of the micrometer-screws in the apparatus — in other words, the 

 way the principle of the micrometer-screws is practically applied. 

 The writer's acquaintance, handling the screw in his turn, sug- 

 gested to the professor the possibility of doubling the delicacy of 

 the scale by letting in another screw within the first, a suggestion 

 that was willingly accepted, and as far as he knows executed. 

 The older young man wants as the basis of enthusiastic exertion, 

 a higher generally practical purpose than merely the routine of 

 manipulation, or the preceding wood and metal work found in 

 some colleges ; besides, he hardly has any time for it ; of course, he 

 submits, but generally, in direct ratio to his intellectual develop- 

 ment, he gets disgusted with the practical drudgery. At that 

 age there is a restlessness of mind, a flight of imagination, an 

 elasticity of thought, that can and ought to be utilized more ad- 



