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An interesting discovery made in recent years in the course of some researches into the traces of the neolithic flint-workers of Norfolk invites attention from the evidence it has been thought to furnish of the traces of a left-handed workman of that remote era.

The Rev. William Greenwell carried out a series of explorations of a number of flint-pits, known as Grimes's Graves, near Brandon, in Norfolk; and in a communication to the Ethnological Society of London on the subject, he states that in clearing out one of the primitive subterranean galleries excavated in the chalk by the British workmen of the Neolithic Age, in order to procure flint nodules in a condition best adapted for their purpose, it was found that, while the pits were still being worked, the roof of the gallery had given way and blocked up its whole width. The removal of this obstruction disclosed three recesses extending beyond the face of the chalk, at the end of the gallery, which had been excavated by the ancient miners in procuring the flint. In front of two of these recesses thus hollowed out lay two picks corresponding to others found in various parts of the shafts and galleries, made from the antlers of the red deer. But Canon Greenwell noted that, while the handle of each was laid towards the mouth of the gallery, the tines which formed the blades of the picks pointed towards each other, showing, as he conceived, that in all probability they had been used respectively by a right and a left-handed man. The day's work over, the men had laid down their tools, ready for the next day's work; meanwhile the roof had fallen in, and the picks were left there undisturbed through all the intervening centuries, till the reopening of the gallery in our own day.

The chronicles of the neolithic miners of Norfolk, as of the greatly more ancient flint-workers of the drift, or the draftsmen of the Dordogne, are recorded for us in very definite characters, more trustworthy, but unfortunately as meagre as other early chronicles. But when we come within the range of written records, or analyse the evidence that language supplies among unlettered races, a flood of light is thrown on the subject of a discriminating choice in use of one or the other hand. The evidence derived from this source leaves no room for doubt that the preferential choice is no mere habit; but that everywhere, among barbarous and civilised races alike, one specific hand has been assigned for all actions requiring either unusual force or special delicacy.

Utque fugam capiant, aries nitidissimus auro Traditur. Ille vehit per freta longa duos. Dicitur informa cornu tenuisse sinistra Femina, cum de se nomina fecit aquae.

THE PRIMITIVE ABACUS

The inferior relation of the left to the right hand was also indicated in the use of the former for lower, and the latter for higher numbers beyond ten. In reckoning with their fingers, both Greeks and Romans counted on the left hand as far as a hundred, then on the right hand to two hundred, and so on alternately: the even numbers being always reckoned on the right hand. The poet Juvenal refers to this in his tenth Satire, where, in dwelling on the attributes of age, he speaks of the centenarian, "who counts his years on his right hand"--

Felix nimirum, qui tot per secula mortem Distulit, atque suos jam dextra computat annos, Quique novum toties mustum bibit.

Ackerman, i. 106.

It is important to keep in view the fact that the relative numbers furnished by the narrative in the Book of Judges do not suggest that the tribe of Benjamin differed in the above respect from other tribes. Of twenty-six thousand Benjamites that drew the sword, there were the seven hundred left-handed slingers, or barely 2?7 per cent, which does not greatly differ from the proportion noted at the present time. In the song of triumph for the avenging of Israel over the Canaanites, in the same Book of Judges, the deed of vengeance by which Sisera, the captain of the host of Jabin, King of Canaan, perished by the hand of a woman, is thus celebrated: "She put her hand to the nail, and her right hand to the workman's hammer; and with the hammer she smote Sisera." Here, as we see, while their deliverer from the oppression of the Moabites is noted as a Benjamite, a left-handed man; Jael, the wife of Heber the Kenite, is blessed above women, who with her right hand smote the enemy of God and her people. Along with those references may be noted one of a later date, recorded in the first Book of Chronicles. When David was in hiding from Saul at Ziklag there came to him a company of Saul's brethren of Benjamin, mighty men, armed with bows, who could use both the right hand and the left in hurling stones and shooting arrows out of a bow. These latter, it will be observed, are noted not as left-handed, but ambidextrous; but this is characteristic of all left-handed persons as an inevitable result of education or compliance with the prevailing usage; though even amongst them the unwonted facility with both hands rarely, if ever, entirely supersedes the greater dexterity of the left hand. Possibly the patronymic of the tribe gave significance to such deviations from normal usage; but either for this or some unnoted reason the descendants of Benjamin, the Son of the Right Hand, appear to have obtained notoriety for exceptional aptitude in the use of either hand.

THE COMPASS POINTS

Among the Romans we may trace some survival of the ancient practice of worshipping towards the east, as in Livy, i. 18, where the augurs are said to turn the right side to the south, and the left side to the north. But the original significance of turning to the east had then been lost sight of; and the particular quarter of the heavens towards which the Roman augur was to look appears to have been latterly very much at the will of the augur himself. It was, at any rate, variable. Livy indicates the east, but Varro assigns the south, and Frontinus the west. Probably part of the augur's professional skill consisted in selecting the aspect of the heavens suited to the occasion. But this done, the flight of birds and other appearances on the right or on the left determined the will of the gods. "Why," asks Cicero, himself an augur, "why should the raven on the right and the crow on the left make a confirmatory augury?" "Cur a dextra corvus, a sinistra cornix faciat ratum?" The left was the side on which the thunder was declared to be heard which confirmed the inauguration of a magistrate, and in other respects the augur regarded it with special awe. But still the right side was, in all ordinary acceptance, the propitious one, as in the address to Hercules --

Salve, vera Jovis proles, pecus addite divis; Et nos et tua dexter adi pede sacra secundo.

Right-handed usages, and the ideas which they suggest, largely influence the ceremonial customs of many nations, affect their religious observances, bear a significant part in the marriage rites, and are interwoven with the most familiar social usages. Among the ancient Greeks the rites of the social board required the passing of the wine from right to left,--or, at any rate, in one invariable direction,--as indicated by Homer in his description of the feast of the gods , where Hephaestus goes round and pours out the sweet nectar to the assembled gods. The direction pursued by the cupbearer would be determined by his bearing the flagon in his right hand, and so walking with his right side towards the guests. This is, indeed, a point of dispute among scholars. But it is not questioned that a uniform practice prevailed, dependent on the recognition of right and left-handedness; and this is no less apparent among the Romans than the Greeks. It is set forth in the most unmusical of Horace's hexameters: "Ille sinistrorsum, hic dextrorsum abit;" and finds its precise elucidation from many independent sources, in the allusions of the poets, in the works of sculptors, and in the decorations of fictile ware.

HANDWRITING

Dr. Guiseppe's attention being thus directed to this aspect of the subject, his next aim was to determine whether the phenomenon might not be physiological, and specially characteristic of left-handed persons; and he naturally reverted to the pathological evidence bearing on left-handed manifestations. He points out that Buchwald, in three cases of aphasia, had found a very peculiar disturbance of written language, which consisted in the fact that the letters were written by the patient from right to left, with reverted slope. He accordingly made further research, with a special view to determine whether this peculiar manifestation was due to morbid causes. Unfortunately, although he states that the subjects of his observation included a considerable number of left-handed persons, the cases stated by him in detail are mainly those of the right-handed who, by reason of injury or loss of the right hand, had been compelled to cultivate the use of the other. Such cases, however, amount to no more than evidence of the extent to which the left hand may be educated, and so made to perform all the functions of the right hand. To one, indeed, familiar by practical experience with the exceptional facilities and the impediments of the left-handed, it is curious to observe the difficulty experienced by a highly intelligent scientific student of the phenomena, to appreciate what seems to the ordinary left-handed man not only natural but inevitable. In the case of Dr. Guiseppe's original patient, he wrote reversely instinctively, and with ease, on the first attempt to use the unfamiliar pen in his left hand. Acquired left-handedness revealed itself, on the contrary, in the writer placing the paper obliquely; or in other ways showing that, with all the facility derived from long practice, it was the result of effort and a persevering contest with nature. Dr. Guiseppe accordingly adds in a summary of results: "In general, I have discovered that right-handed persons who became the subjects of disease affecting the right arm from their infancy were forced to learn to write with the left hand; and they wrote from right to left with sufficient facility, varying the slope of the letters. Those, however, who had become affected with disease in the right arm in adult life, when they had already familiarly practised writing with the right hand, and in consequence of disease had been obliged to resort to the left hand, were less successful in writing with the reversed slope."

To the naturally left-handed person, especially when he has enjoyed the unrestrained use of the pencil in his facile hand, the reversed slope is the easiest, and the only natural one. But this is entirely traceable to the comparatively modern element of cursive writing. No such cause affected the graver, or the hieroglyphic depictor of ideographs, even when reduced to their most arbitrary demotic forms, so long as they were executed singly.

Among another people, of kindred artistic skill, whose records have been brought anew to light in recent years, their monumental evidence appears to furnish more definite results; while the curiously definite reference in the Book of Jonah leaves no room to doubt that among the ancient Ninevites it was recognised that at the earliest stage when voluntary action co-operated with the rational will, a specific hand was habitually in use. That the ancient dwellers on the Euphrates and the Tigris were a right-handed people appears to be borne out by their elaborate sculpture, recovered at Kourjunjik, Khorsabad, Nimroud, and other buried cities of the great plain. The sculptures are in relief, and frequently of a less conventional character than those of the Egyptian monuments, and are consequently less affected by the aspect and position of the figures. The gigantic figure of the Assyrian Hercules--or, as supposed, of the mighty hunter Nimrod,--found between the winged bulls, in the great court of the Palace of Khorsabad, is represented strangling a young lion, which he presses against his chest with his left arm, while he holds in his right hand a weapon of the chase, supposed to be analogous to the Australian boomerang. On the walls of the same palace the great king appears with his staff in his right hand, while his left hand rests on the pommel of his sword. Behind him a eunuch holds in his right hand, over the king's head, a fan or fly-flapper; and so with other officers in attendance. Soldiers bear their swords and axes in the right hand, and their shields on the left arm. A prisoner is being flayed alive by an operator who holds the knife in the right hand. The king himself puts out the eyes of another captive, holding the spear in his right hand, while he retains in his left the end of a cord attached to his victim. Similar evidence abounds throughout the elaborate series of sculptures in the British Museum and in the Louvre. Everywhere gods and men are represented as "discerning between their right hand and their left," and giving the preference to the former.

So far, then, it seems to be proved that not only among cultured and civilised races, but among the barbarous tribes of both hemispheres,--in Australia, Polynesia, among the Arctic tribes of our northern hemisphere at the present day, and among the palaeolithic men of Europe's post-pliocene times,--not only has a habitual preference been manifested for the use of one hand rather than the other, but among all alike the same hand has been preferred. Yet, also, it is no less noteworthy that this prevailing uniformity of practice has always been accompanied by some very pronounced exceptions. Not only are cases of exceptional facility in the use of both hands of frequent occurrence, but while right-handedness everywhere predominates, left-handedness is nowhere unknown. The skill of the combatant in hitting with both hands is indeed a favourite topic of poetic laudation, though this is characteristic of every well-trained boxer. In the combat between Entellus and Dares , the passionate Entellus strikes now with his right hand and again with his left--

Praecipitemque Daren ardens agit aequore toto, Nunc dextra ingeminans ictus, nunc ille sinistra.

But the more general duty assigned to the left hand is as the guard or the shield-bearer, as where AEneas gives the signal to his comrades, in sight of the Trojans --

Stans celsa in puppi; clipeum cum delude sinistra Extulit ardentem.

Thus all evidence appears to conflict with the idea that the preferential employment of one hand can be accounted for by a mere general compliance with prevailing custom. Everywhere, in all ages, and in the most diverse conditions of civilised and savage life, the predominant usage is the same. Not that there are not everywhere marked exceptions to the prevailing practice, in left-handed athletes, handi-craftsmen, artificers, and artists, generally characterised by unusual dexterity; but the farther research is carried, it becomes the more apparent that these are exceptional deviations from the normal usage of humanity.

PSYCHO-PHYSICAL ACTION

The venerable philosopher of Chelsea, musing, with sorrowful experiences to stimulate inquisitiveness, after wondering if any people are to be found barbarous enough not to have this distinction of hands, sums up with the evasion: "Why that particular hand was chosen is a question not to be settled; not worth asking except as a kind of riddle." It seems, however, to be regarded by intelligent inquirers as a riddle that ought to be, and that can be solved, though they have wandered into very diverse courses in search of a solution.

It has been affirmed, for example, that while the right hand is more sensitive to touch, and, as it were, the special seat of the sense of feeling,--as with the right-handed it may well be from constant employment in all operations involving such a test,--the left hand is stated to be the more sensitive to any change of temperature.

Of the occurrence of individual examples of left-handedness the proofs are ample, seemingly from earliest glimpses of life to the present time; and it would even appear that, in so far as the small yet definite amount of evidence of the relative percentage of the left-handed enables us to judge, it differs little now from what it did at the dawn of definite history.

Professor Hyrtl of Vienna affirms its prevalence among the civilised races of Europe in the ratio of only two per cent; and the number of the old Benjamite left-handed slingers, as distinguished from other members of the band of twenty-six thousand warriors, did not greatly exceed this. In the ruder conditions of society, where combined action is rare, and social habits are less binding, a larger number of exceptions to the prevailing usage may be looked for; as the tendency of a high civilisation must be to diminish its manifestation. But education is powerless to eradicate it where it is strongly manifested in early life. My attention has been long familiarly directed to it from being myself naturally left-handed; and the experience of considerably more than half a century enables me to controvert the common belief, on which Dr. Humphry founds the deduction that the superiority of the right hand is not congenital, but acquired, viz. that "the left hand may be trained to as great expertness and strength as the right." On the contrary, my experience accords with that of others in whom inveterate left-handedness exists, in showing the education of a lifetime contending with only partial success to overcome an instinctive natural preference. The result has been, as in all similar cases, to make me ambidextrous, yet not strictly speaking ambidexterous.

The importance of this in reference to the question of the source of right-handedness is obvious. Mr. James Shaw, by whom the subject has been brought under the notice of the British Association and the Anthropological Institute, remarks in a communication to the latter: "Left-handedness is very mysterious. It seems to set itself quite against physiological deductions, and the whole tendency of art and fashion." Dr. John Evans, when commenting on this, and on another paper on "Left-handedness" by Dr. Muirhead, expressed his belief that "the habit of using the left hand in preference to the right, though possibly to some extent connected with the greater supply of blood to one side than the other, is more often the result of the manner in which the individual has been carried in infancy." This reason has been frequently suggested; but if there were any force in it, the results to be looked for would rather be an alternation of hands from generation to generation. The nurse naturally carries the child on the left arm, with its right side toward her breast. All objects presented to it are thus offered to the free left hand; and it is accordingly no uncommon remark that all children are at first left-handed. If their training while in the nurse's arms could determine the habit, such is its undoubted tendency; but if so, the left-handed nurses of the next generation would reverse the process.

While, however, right-handedness is no mere acquired habit, but traceable to specific organic structure, the opinion has been already expressed that it is only in a limited number of cases that it is strongly manifested.

The conclusion I am led to, as the result of long observation, is that the preferential use of the right hand is natural and instinctive with some persons; that with a smaller number an equally strong impulse is felt prompting to the use of the left hand; but that with the great majority right-handedness is largely the result of education. If children are watched in the nursery, it will be found that the left hand is offered little less freely than the right. The nurse or mother is constantly transferring the spoon from the left to the right hand, correcting the defective courtesy of the proffered left hand, and in all ways superinducing right-handedness as a habit. But wherever the organic structure is well developed the instinctive preference manifests itself at a very early stage, and in the case either of decided right-handedness or left-handedness, it matures into a determinate law of action, which education may modify but cannot eradicate.

My colleague, Professor James Mark Baldwin, has followed up my own researches by instituting a systematic series of experiments on his infant daughter, extending over nearly the whole of her first year, with a view to ascertaining definitely the time at which the child begins to manifest any marked preference for either hand. As a specialist in the department of psycho-physics, he carried his inductive research beyond the range embraced in the present treatise; dealing with the question of feelings of efferent nervous discharge or innervation, the motor force of memories of effortless movement, and other conceptions of the psychologist which lie outside of the simpler issue under consideration here. Yet they naturally follow from it; for so soon as volition comes into conscious play, and the hand obeys the mind, and becomes an organ of the will, the psychical element is felt to dominate over the physical; including that very force of will which aims at eradicating the exceptional left-handedness, and enforcing an undeviating submission to the law of the majority.

It is unquestionably of first interest to the psychologist to inquire not only why the child, at the early stage in which a choice of hands is manifested, should prefer the right hand for all strong movements; but also, whether previous experiences in the use of both hands leave behind a sense that the nervous discharge which actuated the right hand was stronger than that which actuated the left. But the point aimed at here is to ascertain the originating physical initiative of determinate action, antecedent to all memory; the precursor of any such action stimulated by memory of an efferent current of discharge of nervous force. For that end the following results, derived from a careful series of observations on the voluntary actions of a healthy child throughout its first year, are of practical significance and value.

" No trace of preference for either hand was found so long as there were no violent muscular exertions made .

" Under the same conditions, the tendency to use both hands together was about double the tendency to use either , the period covered being from the child's sixth to her tenth month inclusive.

" A distinct preference for the right hand in violent efforts in reaching became noticeable in the seventh and eighth months. Experiments during the eighth month on this cue gave, in 80 cases, right hand 74 cases, left hand 5 cases, both hands 1 case. In many cases the left hand followed slowly upon the lead of the right. Under the stimulus of bright colours, from 86 cases, 84 were right-hand cases, and 2 left-hand. Right-handedness had accordingly developed under pressure of muscular effort.

" Up to this time the child had not learned to stand or to creep; hence the development of one hand more than the other is not due to differences in weight between the two longitudinal halves of the body. As she had not learned to speak, or to utter articulate sounds with much distinctness, we may say also that right or left-handedness may develop while the motor speech centre is not yet functioning."

But memory of prior experiences, habit confirmed by persistent usage, and the influence of example and education, all come into play at an early stage, and lend confirmation to the natural bias. The potency of such combined influences must largely affect the results in many cases where the difference in force between the two cerebral hemispheres is slight; and the stimulus to preferential action is consequently weak, as in many cases it undoubtedly is, and therefore not calculated to present any insurmountable resistance to counteracting or opposing influences. Under the term education, as a factor developing or counteracting the weak tendency towards either bias, must be included many habits superinduced not only by the example of the majority, but by their constructive appliances. So soon as the child is old enough to be affected by such influences, the fastening of its clothes, the handling of knife and spoon, and of other objects in daily use, help to confirm the habit, until the art of penmanship is mastered, and with this crowning accomplishment--except in cases of strongly marked bias in an opposite direction,--the left hand is relegated to its subordinate place as a supplementary organ, to be called into use when the privileged member finds occasion for its aid.

But on the other hand, an exaggerated estimate is formed of the difficulties experienced by a left-handed person in many of the ordinary actions of life. It is noted by Mr. James Shaw that the buttons of our dress, and the hooks and eyes of all female attire, are expressly adapted to the right hand. Again, Sir Charles Bell remarks: "We think we may conclude that, everything being adapted, in the conveniences of life, to the right hand, as, for example, the direction of the worm of the screw, or of the cutting end of the auger, is not arbitrary, but is related to a natural endowment of the body. He who is left-handed is most sensible to the advantages of this adaptation, from the opening of the parlour door, to the opening of a penknife." This idea, though widely entertained, is to a large extent founded on misapprehension. It is undoubtedly true that the habitual use of the right hand has controlled the form of many implements, and influenced the arrangements of dress, as well as the social customs of society. The musket is fitted for an habitually right-handed people. So, in like manner, the adze, the plane, the gimlet, the screw, and other mechanical tools, must be adapted to one or the other hand. Scissors, snuffers, shears, and other implements specially requiring the action of the thumb and fingers, are all made for the right hand. So also is it with the scythe of the reaper. Not only the lock of the gun or rifle, but the bayonet and the cartridge-pouch, are made or fitted on the assumption of the right hand being used; and even many arrangements of the fastenings of the dress are adapted to this habitual preference of the one hand over the other, so that the reversing of button and button-hole, or hook and eye, is attended with marked inconvenience. Yet even in this, much of what is due to habit is ascribed to nature. A Canadian friend, familiar in his own earlier years, at an English public school and university, with the game of cricket, tells me that when it was introduced for the first time into Canada within the last forty years, left-handed batters were common in every field; but the immigration of English cricketers has since led, for the most part, to the prevailing usage of the mother country. It was not that the batters were, as a rule, left-handed, but that the habit of using the bat on one side or other was, in the majority of cases, so little influenced by any predisposing bias, that it was readily acquired in either way. But, giving full weight to all that has been stated here as to right-handed implements, what are the legitimate conclusions which it teaches? No doubt an habitually left-handed people would have reversed all this. But if, with adze, plane, gimlet, and screw, scythe, reaping-hook, scissors and snuffers, rifle, bayonet, and all else--even to the handle of the parlour door, and the hooks and buttons of his dress,--daily enforcing on the left-handed man a preference for the right hand, he nevertheless persistently adheres to the left hand, the cause of this must lie deeper than a mere habit induced in the nursery.

It is a misapprehension, however, to suppose that the left-handed man labours under any conscious disadvantage from the impediments thus created by the usage of the majority. With rare exceptions, habit so entirely accustoms him to the requisite action, that he would be no less put out by the sudden reversal of the door-handle, knife-blade, or screw, or the transposition of the buttons on his dress, than the right-handed man. Habit is constantly mistaken for nature. The laws of the road, for example, so universally recognised in England, have become to all as it were a second nature; and, as the old rhyme says--

If you go to the left, you are sure to go right; If you go to the right, you go wrong.

But throughout Canada and the United States the reverse is the law; and the new immigrant, adhering to the usage of the mother country, is sorely perplexed by the persistent wrong-headedness, as it seems, of every one but himself.

Yet the predominant practice does impress itself on some few implements in a way sufficiently marked to remind the left-handed operator that he is transgressing normal usage. The candle, "our peculiar and household planet!" as Charles Lamb designates it, has wellnigh become a thing of the past; but in the old days of candle-light the snuffers were among the most unmanageable of domestic implements to a left-handed man. They are so peculiarly adapted to the right hand that the impediment can only be overcome by the dexterous shift of inserting the left thumb and finger below instead of above. As to the right-handed adaptation of scissors, it is admitted by others, but I am unconscious of any difficulty that their alteration would remove. To Carlyle, as already noted, with his early experiences of country life, the idea of right and left-handed mowers attempting to co-operate presented "the simplest form of an impossibility, which but for the distinction of a 'right hand,' would have pervaded all human things." But, although the mower's scythe must be used in a direction in which the left hand is placed at some disadvantage--and a left-handed race of mowers would undoubtedly reverse the scythe--yet even in this the chief impediment is to co-operation. The difficulty to himself is surmountable. It is his fellow-workers who are troubled by his operations. Like the handling of the oar, or still more the paddle of a canoe, or the use of the musket or rifle,--so obviously designed for a right-handed marksman,--the difficulty is soon overcome. It is not uncommon to find a left-handed soldier placed on the left of his company when firing; and an opportunity--hereafter referred to,--has happily presented itself for determining the cerebral characteristics which accompany this strongly-marked type of left-handedness. As himself incorrigibly left-handed, the author's own experience in drilling as a volunteer was that, after a little practice, he had no difficulty in firing from the right shoulder; but he never could acquire an equal facility with his companions in unfixing the bayonet and returning it to its sheath.

The same facility is illustrated in the varying caligraphy of a letter of Professor Morse, in which he furnished me with the best practical illustration of the ambidextrous skill so frequently acquired by the left-handed. He thus writes: "You will observe that the first page is written with the right hand, the upper third of this page with the left hand, the usual way , the middle third of the page with the left hand, reversed , and now I am again writing with the right hand. As I have habitually used the right hand in writing, I write more rapidly than with the other." In the case of Professor Morse, I may add, the indications of hereditary transmission of left-handedness nearly correspond with my own. His maternal uncle, and also a cousin, are left-handed. In my case, the same habit appeared in a paternal uncle and a niece; and my grandson manifested at an early age a decided preference for the left hand. Even in the absence of such habitual use of both hands as Professor Morse practises, the command of the left hand in the case of a left-handed person is such that very slight effort is necessary to enable him to use the pen freely with it. An apt illustration of this has been communicated to me by the manager of one of the Canadian banks. He had occasion to complain of the letters of one of his local agents as at times troublesome to decipher, and instructed him in certain cases to dictate to a junior clerk who wrote a clear, legible hand. The letters subsequently sent to the manager, though transmitted to him by the same agent, presented in signature, as in all else, a totally different caligraphy. The change of signature led to inquiry; when it turned out that his correspondent was left-handed, and by merely shifting the pen to the more dexterous hand, he was able, with a very little practice, to substitute for the old cramped penmanship an upright, rounded, neat, and very legible handwriting.

In those and similar cases, the fact is illustrated that the left-handed person is necessarily ambidextrous. He has the exceptional "dexterity" resulting from the special organic aptitude of the left hand, which is only paralleled in those cases of true right-handedness where a corresponding organic aptitude is innate. Education, enforced by the usage of the majority, begets for him the training of the other and less facile hand; while by an unwise neglect the majority of mankind are content to leave the left hand as an untrained and merely supplementary organ. From the days of the seven hundred chosen men of the tribe of Benjamin, the left-handed have been noted for their skill; and this has been repeatedly manifested by artists. Foremost among such stands Leonardo da Vinci, skilled as musician, painter, and mathematician, and accomplished in all the manly sports of his age. Hans Holbein, Mozzo of Antwerp, Amico Aspertino, and Ludovico Cangiago, were all left-handed, though the two latter are described as working equally well with both hands. In all the fine arts the mastery of both hands is advantageous; and accordingly the left-handed artist, with his congenital skill and his cultivated dexterity, has the advantage of his right-handed rival, instead of, as is frequently assumed, starting at a disadvantage.

CONFLICT OF THEORIES

The inevitable conclusion forced on the inquirer is that the bias in which this predominant law of dexterity originates must be traceable to some specialty of organic structure. On this assumption one feature in the anatomical arrangement of the most important vital organs of the body presents such a diversity in their disposition as would seem to offer a sufficient cause for greater energy in the limbs on one side than on the other, if accompanied by exceptional deviations from the normal condition corresponding to the occurrence of left-handedness; and in this direction a solution has accordingly been sought. The bilateral symmetry of structure, so general in animal life, seems at first sight opposed to any inequality of action in symmetrical organs. But anatomical research reveals the deviation of internal organic structure from such seemingly balanced symmetry. Moreover, right or left-handedness is not limited to the hand, but partially affects the lower limbs, as may be seen in football, skating, in the training of the opera-dancer, etc.; and eminent anatomists and physiologists have affirmed the existence of a greater development throughout the whole right side of the body. Sir Charles Bell says: "The left side is not only the weaker, in regard to muscular strength, but also in its vital or constitutional properties. The development of the organs of action and motion is greatest upon the right side, as may at any time be ascertained by measurement, or the testimony of the tailor or shoe-maker." He adds, indeed, "Certainly this superiority may be said to result from the more frequent exertion of the right hand; but the peculiarity extends to the constitution also, and disease attacks the left extremities more frequently than the right."

With the left-handed, the general vigour and immunity from disease appear to be transferred to that side; and this has naturally suggested the theory of a transposition of the viscera, and the consequent increase of circulation thereby transferred from the one side to the other. But the relative position of the heart is so easily determined in the living subject, that it is surprising how much force has been attached to this untenable theory by eminent anatomists and physiologists. Another and more generally favoured idea traces to the reverse development of the great arteries of the upper limbs a greater flow of blood to the left side; while a third ascribes the greater muscular vigour directly to the supply of nervous force dependent on the early development of the brain on one side or the other.

So far as either line of argument prevails, it inevitably leads to the result that the preference of the right hand is no mere perpetuation of convenient usage, matured into an acquired, or possibly an hereditary habit; but that it is, from the first, traceable to innate physical causes. This, as Sir Charles Bell conceives, receives confirmation from the fact already referred to, that right or left-handedness is not restricted to the hand, but affects the corresponding lower limb, and, as he believes, the whole side; and so he concludes thus: "On the whole, the preference of the right hand is not the effect of habit, but is a natural provision; and is bestowed for a very obvious purpose." Nevertheless, the argument of Sir Charles Bell is, as a whole, vague, and scarcely consistent. He speaks indeed of right-handedness as "a natural endowment of the body," and his reasoning is based on this assumption. But much of it would be equally explicable as the result of adaptations following on an acquired habit. Its full force will come under consideration at a later stage. Meanwhile it is desirable to review the various and conflicting opinions advanced by other inquirers.

The theory of Dr. Barclay, the celebrated anatomist, is thus set forth by Dr. Buchanan, from notes taken by him when a student: "The veins of the left side of the trunk and of the left inferior extremity cross the aorta to arrive at the vena cava; and some obstruction to the flow of blood must be produced by the pulsation of that artery." To this Dr. Barclay traced indirectly the preferential use of the right side of the body, and especially of the right hand and foot "All motions," he stated, "produce obstruction of the circulation; and obstruction from this cause must be more frequently produced in the right side than the left, owing to its being more frequently used. But the venous circulation on the left side is retarded by the pulsation of the aorta, and therefore the more frequent motions of the right side were intended to render the circulation of the two sides uniform." The idea, if correctly reported, is a curious one, as it traces right-handedness to the excess of a compensating force for an assumed inferior circulation pertaining naturally to the right side; and incidentally takes into consideration an abnormal modification affecting the development or relative disposition of organs. Both points have been the subject of more extended consideration by subsequent observers. It is curious, indeed, to notice how physiologists and anatomists have shifted their ground, from time to time, in their attempts at a solution of what has been very summarily dismissed by others as a very simple problem; until, as Dr. Struthers remarks, it "has ceased to attract the notice of physiologists only because it has baffled satisfactory explanation."

The eminent anatomist, Professor Gratiolet, turned from the organs in immediate contact with the arm and hand, and sought for the source of right-handedness in another and truer direction, though he failed to realise its full bearings. According to the Professor, in the early stages of foetal development the anterior and middle lobes of the brain on the left side are in a more advanced condition than those on the right side, the balance being maintained by an opposite condition of the posterior lobes. Hence, in consequence of the well-known decussation of the nerve roots, the right side of the body,--so far as it is influenced by brain-force,--will, in early foetal life, be better supplied with nervous force than the left side; and thereby movements of the right arm would precede and be more perfect than those of the left. The bearings of this line of argument in its full compass will come more fitly under review at a later stage.

Dr. Andrew Buchanan, Professor of Physiology in the University of Glasgow, in a paper communicated by him to the Philosophical Society of Glasgow in 1862, entitled "Mechanical Theory of the predominance of the right hand over the left; or more generally, of the limbs of the right side over those of the left side of the body," aimed at a solution of the question in a new way. According to him, "the preferential use of the right hand is not a congenital but an acquired attribute of man. It does not exist in the earliest periods of life." Nevertheless, "no training could ever render the left hand of ordinary men equal in strength to the right;" for "it depends upon mechanical laws arising out of the structure of the human body." This theory is thus explained: In infancy and early childhood there is no difference in power between the two sides of the body; but so soon as the child becomes capable of bringing the whole muscular force of the body into play, "he becomes conscious of the superior power of his right side, a power not primarily due to any superior force or development of the muscles of that side, but to a purely mechanical cause. He cannot put forth the full strength of his body without first making a deep inspiration; and by making a deep inspiration, and maintaining afterwards the chest in an expanded state, which is essential to the continuance of his muscular effort, he so alters the mechanical relations of the two sides of his body that the muscles of his right side act with a superior efficacy; and, to render the inequality still greater, the muscles of the left side act with a mechanical disadvantage." Hence the preference for the right side whenever unusual muscular power is required; and with the greater exercise of the muscles of the right side their consequent development follows, until the full predominance of the right side is the result.

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