806 TRANSACTIONS OF SECTION L. 



separately when the disc is rotating slowly, but as the speed of the disc is 

 gradually increased a point is reached when the two colours fuse into one uniform 

 tint. This critical speed is a measure of the perseveration of the subject being 

 tested. 



Gross has shown theoretically how the mental character of the subject may be 

 deduced from his or her perseveration, and the experiments made by Wiersma and 

 others agree very closely with Gross's theoretical deductions. Perseveration 

 indicates the quality of the intelligence rather than its amount ; persons with high 

 perseveration may be described as slow-intelligent, and those with low persevera- 

 tion as quick-intelligent. There is a considerable range of perseveration among 

 normal persons, but when it passes above or below certain limits it is usually 

 associated with insanity of different kinds. Acute maniacs have abnormally low 

 and melancholies abnormally high perseveration. A description was given of an 

 improvement on Wiersma's disc devised by the author, in which illuminated 

 coloured glasses are reflected into the eye of the subject by a revolving mirror. 

 This enables the luminosity of the colours to be regulated. Results of tests 

 made by the author on visitors to the exhibitions at the White City were 

 given, and an interesting hypothesis on the connection between perseveration and 

 colour blindness. 



8. Experimental Work on Intelligence. By H. S. Lawson. 



Experiments have been performed on groups of boys between the ages of 

 nine and sixteen. These groups are as follows : — 



(a) Elementary-school boys who were within two months of nine years on 



January 1, 1909. (I.) 

 (6) Elementary-school boys who presented themselves for a scholarship 



examination at a Midland grammar school. Age limit, thirteen years. 



(II.) 

 (c) Students in the same grammar school. (Ill) 



I. These boys have been submitted to twelve tests of intelligence, each of 

 which has been given for a period of from three to twenty days. In every case 

 the functioning of the higher mental levels is involved. The correlations between 

 the various methods of diagnosing intelligence have been arranged in the form of 

 a hierarchy, wherein that test which has been proved objectively to be most 

 intellective in nature takes first place. 



II. These candidates were submitted to simple tests of intelligence at the 

 close of the official scholarship examination. The coefficient of correlation 

 between official and unofficial (the present writer's) order of merit was, in 1909, 

 0"217, and, in 1910, 0'485. The similarity of position was most marked in the 

 upper strata. The coefficient for the ' 1910 ' examination was higher than that 

 which obtained between any two individual orders of merit in the official examina- 

 tion. In the latter, examination papers were set in arithmetic, history, geography, 

 grammar, composition, and dictation. 



III. Several classes in the grammar school have from time to time been given 

 exercises to perform, in which processes of reasoning are involved. An amal- 

 gamated order of merit for the several forms has been produced. The coefficient 

 of correlation between these respectively and the term's order for the various 

 classes engaged has been calculated. In every instance a high number has been 

 obtained. 



The career of the scholarship students is being watched. Public examinations 

 are a useful criterion whereby to gauge the relative merits of the two methods 

 of ' spotting ability ' outlined in this abstract. 



9. M. Binet's Method for the Measurement of Intelligence. 

 By Miss Katharine L. Johnston. 



With M. Binet's help given at the Laboratory, Rue Grange aux Belles, Paris, 

 I have applied his tests for estimating the level of intelligence to 200 school 

 girls of Sheffield. 



The tests are part of a more extensive examination which has as its object 



