278 LINUS WARD KLINE 



that the ability to chart the boxes is a function of speed. The 

 short life of the imagery for the position of the boxes, before the 

 achievement of the higher rates of speed, indicate that fact. 

 Rapidity in memorizing the positions seems to depend on differ- 

 ences in attitudes and in modes of attacking the problem. The 

 ready recognition and use of minor aids throughout the learning 

 was distinctly an individual trait and showed great variation 

 among the subjects. 



Conscious efforts were directed: first, to learning the four 

 corner boxes; second, to filling in the four sides or edge boxes; 

 third, to locating the inner boxes with reference to the edge 

 boxes (and here those adjacent had an advantage, while those 

 further in were located by the number of boxes removed from 

 the side and from the end); fourth, to grouping the boxes of the 

 same number bearing different suits; fifth, to fixing the box by 

 the value of its cards in certain games; sixth, to locating con- 

 tiguous boxes correlated with sequential movements (pairing the 

 boxes) ; seventh, to locating boxes that were the termini of long 

 sweeping movements. 



Since the maps were made at every period until final comple- 

 tion, it was possible to arrange the results in a time series and 

 thereby show the growth of place memory. In table 2 the series 

 is thus arranged under the caption Rt. (right location), and an 

 inspection of this column shows that, when the number reaches 

 39 the number of boxes used the rate of distribution, with a 

 few exceptions, rapidly increases; the column headed "rate" in 

 table 2 shows this. 



Since place-memory is a temporary function of skillful move- 

 ments, it is necessary to see if there is any causal relation be- 

 tween the nature of a movement, and the growth of such mem- 

 ory for the point toward which the movement is made. For 

 this purpose the time order in which each box was first located 

 by all the subjects was determined, and then the probable causes 

 for such priority examined. 



The time order in which a box was located by all subjects was 

 done by counting the number of correct locations given a card 

 by all subjects taken collectively at the same period. 



