Miscellanea 
177 
diminish witli experience of maze-tracing. It is probable that the mathematicians had at first an 
advantage which was not maintained. It may be suspected that they reahsed better at the outset 
what was required ; an appreciation also of time taken may have been a factor at the outset with 
the musicians. But both these advantages seem to diminish as the non-mathematical and non- 
musical gain experience. The above remarks refer to the total correlations; when corrected for 
age we see that the conclusions for steadiness of hand are confirmed ; even for constant age it has 
no sensible relationship to either mathematical or musical capacity. Rapidity of hand does show 
relationship with mathematics in a more marked, and with music in a less marked degree when we 
correct for age. But again both the associations are lessening with experience; for the third maze 
the superiority of the good mathematicians is only very moderate and the superiority of the good 
musicians has become insensible. There can be little doubt that the more marked superiority 
for Maze I was due to a better appreciation of what was needed in a novel task. 
(7) Conclusions. The material dealt with is admittedly slender, and was analysed only as a stejj 
towards more elaborate returns ; it was made in order to determine what additional experiments 
should be tried. Our conclusions are therefore suggestive rather than dogmatic. We have not 
been able to associate in a marked degree rapidity and steadiness of hand as exhibited in maze- 
tracing with any training ; we more than suspect them to be innate characteristics *. Good craft, 
mathematical ability and musical capacity seem to some not very marked extent associated with 
rapidity of hand, but it is noteworthy that even in these cases the advantage was rather an initial 
one and tended to weaken with experience. An apparently noteworthy point, which is well worth 
confirmation or contradiction, is that continued training may only just suffice to maintain a grade 
of efficiency, which deteriorates with age. It would be of much interest to demonstrate that 
training in some cases does not create or even develop a faculty, but maintains it at the higher 
range of efficiency which belongs to an earlier age. It is possible that the teacher cannot develop 
imagination in the later stages of youthful growth, but may be able to preserve the greater 
imagination of the child by proper training. Certain faculties may be most intense at certain 
stages of growth. If education seizes upon them at this age and maintains their then intensity, 
we may be apt to overlook their history, and suppose them created by the educational process. 
The point is worth a direct and more intensive investigation. Here it is only a suggestion. 
I have to thank Professor Pearson for his assistance during the preparation of this paper. 
II. Sur les moments de la fonction de correlation normale de 
n variablesf. 
Par SVERKER BERGSTROM, Stockholm. 
1. La fonction dc correlation normale de n variables pent s'ecrire d'apres le theoreme celebre 
de M. Pearson J 
Z= 6 2iJ„^i,r,<rp<r/'^ " (1), 
(27i-)2o-iO-j ... cr„ V« 
[* After thirty years' experience in teaching in a drawing office I think it safe to say that within a 
fortnight it is possible to assert of the bulli of freshmen engineers whether or no they will be good 
draughtsmen at the end of their two to three years' course. The power of rapid, steady, uniform bold 
work is there in germ or it is not. Knowledge of method and accuracy of result may be acquired, but 
only to a minor extent can anyone acquire that which distinguishes a good from a mediocre draughts- 
man. K. P.] 
[f The present paper reached the editor later than the three other memoirs dealing with allied tojjios 
published in this part of the Jqurnal, but the methods adopted are of sufficient interest to justify its 
appearance in association with those papers.] 
X Voir K. Pearson, Phil. Trans, t. 187 (1896) et t. 200 (1903). 
Biometrika xii 12 
