Validity of Ergo graph as Measurer of Work Capacity 27 



day were thought to be a pretty severe task, and a rest period of 

 four days was again taken, constituting the second rest period. 

 When work was resumed the records of M., as the table shows, 

 presented an increase equivalent to nearly one-fourth. On the 

 last day before the work was suspended the mask for the right 

 hand of B. was broken, and it was some days before a new one 

 could be made to fit well. The one that was used was extremely 

 painful, and the reagent was unable to reach anything near the 

 maximum attained during the second period of work. Even the 

 left hand during the same period showed no practice gain what- 

 ever. 



As two records had been thought to be a pretty severe task, 

 the reagents feeling more or less exhausted by evening, only a 

 record a day with either hand was taken during the first five 

 days of the third period. The records of M. during the third 

 period, which continued for ten days, show with some fluctua- 

 tions a steady practice gain, 12.6 mm. average performance 

 increase for the right hand and 38.8 mm. for the left. The 

 records of the left hand actually exceeded the records of the 

 right upon two occasions. 



Since the records after the first two rest periods 1 showed a 

 considerable increase over those taken just before the rest, prov- 

 ing that no loss of practice effect had taken place, the work was 

 again suspended for six days, with a view of testing further the 

 question of practice loss. The average daily performances dur- 

 ing the third series are almost double the same averages for the 

 first period. 



The average for the four records for M.'s right hand just 

 previous to the third rest was 1770 mm. and for the four just 

 after, 1785.5 mm., and of the left hand for the four before the 

 third rest 1636.7 mm. and for the four after, 1880.5 mm - Dur- 

 ing the rest the right hand had thus gained slightly and steadily 

 in power, and the left very considerably. So far as the apparent 

 bodily condition was concerned, inurement and habituation had 

 become complete, for no uncomfortable effects of any kind 

 seemed to remain after observations during the third period of 



1 Amberg: Ueber den Einfluss von Arbeitspausen auf die geisUge Leis- 

 iungsfaehigkeit. Psychologische Arbeiten (Kraepelin), 1896, Band 1, s. 30. 



I05 



