The daily morning journal and courier., 1905-05-25


 ProeIIytty.
 That the great majority of persons use the right hand with greater skill than the left is doubtless due to two infuences-an innate proclivity and constant practice. The preference shown by most infants at the age of one year for the use of the right hand proves that there is an inherited tend ency. Further evidence of it is found in the greater ease with which any en- tirely new act is performed by the right than by the left hand. Training, how ever, is an important factor. A mature person, having lost the right hand by accident, can achieve wonders with the other if he only exercises patience, perseverance and strong will.
 The more mysterious of the two fac- tors in this problem is the inborn tend ency. How did it arise? There are exceptions to the rule. Perhaps two out of every hundred babies are left hand. But when you stop to think of it the natural inclination of the other ninety-eight is remarkable. A great many physiologists have speculated in regard to it's cause without reaching any conclusion upon which all could agree.
 Dr. George M. Gould says in the Popular Science Monthly that right handedness is so thoroughly ingratiat- ed in human nature that it must have been partially developed in the savage ancestors of the race. Primitive man, 1 in his opinion, must have felt definate need for the exercise of his right hand in preference to his left, and that ne- cessity must have been recognized and lobeyed for a long period continuously, The impulse could not well have die tated his habits in eating, for knives and forks are of recent origin, the modern gun had not been invented, and writing was practically unknown | Moreover, in such operations as chip ping arrowheads, weaving baskets and l yielding clubs, bow, and arrows it could not have mattared much which i hand was imployed. | When warfare had been carried to such a stage of advancement as to in ivolve the use of a shield, however, that gobject was probably held on the left I side in order to protect the heart. l Then as a matter of convenience the ] right arm was left free for the more active function of fighting with spear and sword, and with habitual exer- 4 else came special skill. An attendant 1 phenomenon was a finer organization l of that particular center in the brain which controlled these movements and which was situated in the left half of the organ. The brain is the real seat of all dexterity, and something takes place there in correspondence with ex- I ternal efficiency. With an increased use of the right hand, Dr. Gould thinks | there must have been greater demands ] upon the right eye, because vision must precede the order to strike or to give peaceful signals. In this way there may have been developed a keener power of vision in the right eye than ' in the left Dr. Gould assumes that there vast and declares that right i handed people are right eyed" and that in their brains the center of vision is on the left side, in close proximity to ! that governing the right arm.
 While civilization was yet at a low llevel communication was carried on, especially with strangers, largely in Etha signa language Barter laid the .t Foundations of arithmetic and called t into play the digits. The preference already given to the right hand in bat tile may have guided men in the choice .s,1 social cermonies. Computation, pr. Gould points out, was an intellectual ! process which was conducted in the fspeech center c the brain. Nature was l compelled to take sides in locating the aE latter, and she placed it to the left of the middle. Dr. Gould thinks that the lchoice was governed by the employ
 ment of the right hand for giving sig inals. So irltemately related are the functions of speech and vision and the control of the muscular efforts with the right arm that action would be
 quicker if the cerbral centers control
 ling them were closely associated
 j Before discussing the cause of left E Ehandedness Dr. Gould calls attention to 5 the fact that with right handed peo- Hple the left hand is occasionally call led upon to perform a task of greater importance than it's mate. In eating H the fork is used more than the knife i In playing a violin or violoneello the lingering is done with the left hand
 and the lowing with the right. It is ff suggested that some of these opera
 tions may result from the superiority
 of the right eye. Perhaps the laatel can watch and guide them better when they are performed with the Jeff
 than with the right hand. }' % I Left handedness is considered by Dr 2 Gould an inheritance from ancestors
 savage or civilized, who were obliged by some misfortune to abandon tht
 use of the right hand. An even more influential injury, he thinks, would d have been as to the right eye. Witl
 the cultivation of skill with he lief hand, he believes, there followed :
 change in the organization of the brair
 Owing to the center, which had for
 merly controlled action, lost its vigo
 and that on the opposite side acouir
 ed increased power. pr. Gould say
 that the speech center was also trans < Eferred from the left side to the righ Eof the brain in consequnce. In th' transmission of the cerebral peculiarit. tof off -sring he finds the key to tn manifestation of left handedness at ; . | T 1,ly UN,,ih ht1I,n