384 THE NEW WORLD OF SCIENCE 



" Similarly, in an oral test for horseshoers, the soldier is 

 asked such questions as these : 



" 4 How does a deep-seated corn usually show on a sole ? ' 

 ' Red/ is the answer which experienced horseshoers univers- 

 ally give to this answer. 



'* l What is the fullering in a shoe ? ' ' Groove * and * crease ' 

 have both been found to be acceptable answers. 



'* ' How do you shoe a horse that has a bone spavin ? ' 

 ' Lower the toe and raise the heels/ 



" Questions likely to provoke narration of processes or de- 

 scriptive answers that are both time-consuming and difficult to 

 evaluate, are omitted. Only those questions are included which 

 seem simple, clear, direct and unambiguous, and which promise 

 to elicit answers that can be accurately scored and that will be 

 genuinely diagnostic of trade proficiency. 



" After a tentative test containing sixty, eighty, or even a hun- 

 dred distinct elements has been assembled it must be tried out. 

 It is first used in testing from five to twenty men whose high 

 proficiency in the trade is known. During this preliminary 

 tryout the test undergoes progressive revision and refinement. 

 Ambiguities and localisms of terminology are eliminated. Ele- 

 ments that require too much time or that prove to be repetitive 

 of other elements, or that are not sufficiently diagnostic, are 

 dropped. 



" The revised test is now subjected to a second and much 

 more thorough tryout. With adherence to rigorously uniform 

 procedure, it is administered in various establishments and in 

 different industrial regions of the country, to no less than eighty 

 men whose proficiency is known. Of these, twenty are experts 

 in the trade, twenty are journeymen, and twenty are men rated 

 as apprentices of at least fourteen months and less than three 

 years' standing. The remaining twenty are novices, persons of 

 good education and intelligence but with no experience at the 

 trade in question. The testing of these novices is necessary in 

 order to discover and eliminate the elements of the test which 



