48 THE POPULAR SCIENCE MONTHLY. 



reasoning. When the boys came to study plants, minerals, and 

 insects they found their knowledge of Euclid gave them a new 

 and vital thread whereon to stiing what they learned. This was 

 even more decidedly the case when they came to study the various 

 modes of motion and certain principles of engineering science. 

 Mr. W. G. Spencer, the father of Herbert Spencer, in an invalu- 

 able little book * has shown how geometry can be taught so as" to 

 educe the noble faculty of invention. At the high school at 

 Yonkers, New York, of which Mr. E. R. Shaw is principal, I have 

 seen most original and beautiful solutions of Mr. Spencer's prob- 

 lems worked out by the pupils. 



THE LOGIC OF FREE TRADE AND PROTECTION. 



By ARTHUR KITSON. 



IN an interesting chapter on the history of tariff legislation 

 Mr. Blaine, in his Twenty Years in Congress, thus presents 

 the issue : 



" It is natural that both sides of the tariff controversy should 

 endeavor to derive support for their principles from the experi- 

 ence of the country. Nor can it be denied that each side can 

 furnish many arguments which apparently sustain its own views 

 and theories. The difficulty in reaching a satisfactory and im- 

 partial conclusion arises from the inability or unwillingness of 

 the disputants to agree upon a common basis of fact. If the 

 premises could be candidly stated, there would be no trouble in 

 finding a true conclusion. In the absence of an agreement as to 

 the points established, it is the part of fairness to give a succinct 

 statement of the grounds maintained by the two parties to the 

 prolonged controversy grounds which have not essentially 

 changed in a century of legislative and popular contention." 



This presentation of the case describes precisely the difficulty 

 under which all discussions on the tariff question in this country 

 have hitherto labored. We believe, however, the difficulty in 

 agreeing upon a common basis is one of inability rather than 

 one of unwillingness ; for, where facts are contradictory, how is 

 it possible to establish a common basis ? The advocates of two 

 opposite and distinctly contradictory theories can scarcely be ex- 

 pected to find a common basis of fact in a collection of instances 

 which favor both theories. In such a case it would be reasonable 

 to suppose one of two things : either that the theories were per se 

 insufficient to account for the given effect, or that they were 



* Inventional Geometry. D. Appleton & Co., New York. 



