DEXTRALITY AND SINISTRALITY. 363 



functions, a differentiation of ability, than a unique one. In the dextral 

 the left hand does many tasks of as great or greater importance, and 

 with equal or superior skill, as the right. In eating, the fork is now 

 more used than the knife ; in gunning, the left hand is given the vastly 

 more important, difficult and onerous task ; in chopping, hoeing, shovel- 

 ing, picking, lathe-work, railway locomotive engineering and other 

 tasks the left arm and hand often execute the chief and more expert 

 tasks. Especially noteworthy is the playing of the violin, 'cello and 

 bass viol. The ' fingering ' is done with the left hand, and forms a 

 striking reversal of dextrality, because it is hy all odds the function 

 requiring more manipulative skill, accuracy and rapidity. I do not 

 know that the fact itself has ever been observed and stated, but cer- 

 tainly the reason of this strange contradictory practise has hitherto 

 escaped the attention. It is, I think, due to dextrocularity. With 

 few and easily explained exceptions dextromanuality is a result, or a 

 concomitant, of dextrocularity. If the violin, 'cello and viol were 

 fingered with the right hand the learner would be greatly handicapped 

 by the foreshortening which would exist as his dextral eye glanced 

 along the neck of the instrument straight in front or below this eye. 

 The learner must see his fingers and gain precision in placing them by 

 careful visual estimates. But when placed sinistrad the right eye sees 

 the neck of these instruments and the fingers at an angle which per- 

 mits more accurate observation, estimates of distances, etc., than would 

 be possible if the instrument were fingered with the right hand. In 

 those instruments necessarily held in the median line, some wind- 

 instruments, the flageolet, hautboy, etc., the right hand asserts its 

 selective and more difficult task. When the hands are not seen at all, 

 as in the flute, fife, etc., the right again has its choice. No pupil with 

 sinistromamiality established can learn piano-playing easily. I know 

 of one who was a great lover of music who failed utterly after long 

 perseverance. 



There are other cautions to be emphasized relating to the acquire- 

 ment of dextrality by the savage : Nearly all the actions which we now 

 call right-handed were in primeval times to him unknown. This is 

 especially true of three things. Knives and forks have only been used 

 in eating for a few hundred years. He ate with his fingers, and one 

 may suspect he used the left as much as the right in this way. The 

 Mussulman custom and its reason are, of course, both modern. 

 Secondly, the modern gun and revolver had not been devised. The 

 bow and arrow, the spear, boomerang, club, etc., could be used as well 

 with the left hand by the sinistromanual. Thirdly, writing was un- 

 known, or relatively so, and, as we have now learned, that locates the 

 speech center in the cerebral hemisphere opposite the writing hand. 

 It is thus evident that dextrality in the savage, at the time when it 



