E. Schuster 
43 
The correlations were in this case : 
Age 18 r = -19 Age 21 r = '24 
Age 19 r = -08 Age 22 r = '02 
Age 20 r = "19 Average ? , = , 14 
Here the correlation is lower than in the case previously considered, but again is 
positive in every group. 
As it had been suggested to me that the test might be effected by eyesight, 
the correlations with acuity of vision were determined and are here shown : 
Age 18 r = - -06 Age 21 r = + 'll 
Age 19 r = - '04 Age 22 r = - 01 
Age 20 r = — *12 Average r = — "02 
The minus signs indicate a negative correlation, i.e. that bad eyesight shows to 
slight advantage, but since the numerical values are very small and the sign is 
not constant throughout, it may be concluded that eyesight does not appreciably 
affect the results of this test. 
(2) Acuity of Vision is tested by means of a card on which are printed ten lines 
of type of heights ranging from rather over 4^ inches in the top line to ^th inch 
in the bottom line. The height of the type is so adjusted that it subtends an 
angle of five minutes in the eye at the following distances : 
Top line . . . 
6th line 
... 9 metres 
2nd „ ... 
36 „ 
7th „ ... 
... 6 „ 
3rd „ 
... 24 „ 
8th „ 
... 4 „ 
4th „ 
... 18 „ 
9th „ 
... 3 „ 
5th „ , 
... 12 „ 
10th „ 
... 2 „ 
A person with normal sight should be able to read each line at the distances 
named with each eye separately. Since the card is shown to the subject at a 
distance of six metres, he should be able to read down to the seventh line. As a 
matter of fact, a considerable number of men can read accurately with either eye 
as far as the ninth line ; but we have not as yet found anyone who can get as far 
as the tenth. 
In recording the results of this test, the smallest type which can be read is 
noted and the distance at which it should be read by a person of normal sight is 
entered in the schedule. For example, if the entry stands " Right Eye 80, Left 
Eye 36," it means that the subject, standing at a distance of six metres from the 
card, can read the top line only with his right eye and the second line also with 
his left. A person of normal sight could have read these at distances of 80 and 
36 metres respectively. (£) entered against the number signifies that only a 
certain proportion of the letters in the line referred to were read correctly. 
6—2 
