THE TECHNIQUE OF GIVING TESTS 
165 
modify it until directions can be given which shall cover 
J ts scope of possibilities. The simplest solution of this 
problem is to perfect a test until it is self-explanatory. 
That is, make the test so perfect that it can be given with 
a minimum of directions. The most successful tests in 
this respect are the form-board tests and the machine 
operator’s test. When a form board is placed in readiness 
before a subject, it is almost possible to comprehend the 
task to be performed without any oral directions. The 
empty spaces in the "board are apparent, and the pieces are 
there. Nothing is more natural than to pick up the pieces 
ar ffi put them in the spaces where they seem to belong. 
Jm the machine operator’s test described in Chapter X, 
’t is perfectly obvious that the task is to drop the steel 
balls through the opening at the proper instant. 
In the performance of the tests themselves, there are 
many details to be watched. When the assembling tests 
w ere being given to assemblers, one of the difficulties to be 
overcome was due to the oil which clung to the hands of 
those who were assembling oily parts. The men taking 
the form board test which requires placing triangles into 
their proper spaces frequently had difficulty because this 
°h caused the very small triangles to stick to their fingers, 
taking it very difficult to do the act quickly. The same 
difficulty is likely to arise in warm weather, due to hands 
that are moist with perspiration. It is advisable, there 
fore, always to have a good wiping and drying cloth at 
hand, so that those who are being tested may not suffer 
bom an unnecessary handicap. 
Another point which may seem quite trivial but which is 
Ver y important is the use of pencils. In every test which 
does not depend entirely upon the subject’s ability to 
handle a pet pen, it is advisable to use pencil. The pencils