July 16, 1909] 



SCIENCE 



75 



tise, was ordered to run a line of levels. 

 He declined to use the instrument given 

 him, saying that he had tried to adjust it 

 and found an inherent defect which would 

 vitiate his work; and, as it was a line 125 

 miles long in a bad country, he could not be 

 responsible for correct results. He was 

 commended for his discretion, given a bet- 

 ter instrument, completed the task, and be- 

 fore the end of the year was made assistant 

 engineer with an office in a railroad center. 

 You will say that this is only ordinary cau- 

 tion. True ; but many fail at such a point. 

 Others had heedlessly used that instru- 

 ment without proving it, probably on the 

 assumption that a level is a level, and must 

 do the W'Ork in some way. Again, a young 

 graduate on the reclamation service was 

 marked for enforced vacation, when the 

 contractors had failed and work was cur- 

 tailed. But his chief said, "No, I want to 

 keep him: somehow he always gets results 

 and has them right!" 



As tending to thoroughness also we may 

 state as principle (6) : "Do not have too 

 many irons in the fire at once." For the 

 average man in a professional course, about 

 two subjects followed collaterally are 

 enough to engage all of his interest and en- 

 thusiasm. This does not rule out one other 

 for culture or relaxation, but that should 

 be according to his own preference and at 

 odd times. Any overburden tends to pro- 

 duce distraction and mental worry, which 

 impair the average accomplishment. Dis- 

 persion of the stream in an alluvial chan- 

 nel makes shoal water, concentration 

 makes deep water. 



Working on this principle of concentra- 

 tion along two lines secures better con- 

 tinuity and more sustained interest in a 

 given subject; also it makes more feasible 

 the policy of individual instruction, by not 

 restricting the sessions in class-room or 

 laboratory to a set period of minutes or 



houre. The speaker has used for many 

 years the half-day as a unit period, 

 whether the assignments are for recitation, 

 field-work or laboratory. 



In this principle also is included the ne- 

 cessity of judiciously excluding all non-es- 

 sentials. The body of engineering litera- 

 ture is now so overwhelming in its quantity 

 and range that the most diligent student 

 can only get a glimpse of it; but he can 

 learn to use the indexes and make his own 

 card catalogue, through required reports 

 on assigned topics; also how to unlock the 

 storehouse ; how to make his knowledge and 

 elementary skill effective in emergencies. 



We have noticed how largely the engi- 

 neering profession utilizes the results of a 

 wide range of scientific investigation. 

 This gives apparent complexity ; hence the 

 division into the several recognized 

 branches. Yet it is no contradiction to as- 

 sert that a second characteristic of engi- 

 neering education is the domination of a 

 comparatively few controlling principles 

 and methods. 



If the members of the graduating class 

 will take a retrospect of their entire four- 

 years ' course they may be surprised to find 

 how much it can be boiled down to a not 

 very large residuum of fundamental prin- 

 ciples and data. In the applications of 

 mathematics the really important subjects 

 of engineering employ chiefly the more 

 simple rules, methods and formulae of 

 arithmetic, algebra, geometry (including 

 the analytical), trigonometry and calculus. 

 The more intricate formulte and the higher 

 theorems are not extensively used even in 

 mechanics of materials, theory of framed 

 structures and hydraulics. The interesting 

 applications of the theory of the higher 

 plane curves in mechanism and macliine 

 design are almost the poetry of mathe- 

 matics. The entire science and method of 

 the graphic statics is plain application ef 



