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Show LEAVE HIM ALONE, Insists Educator Who by Tests of 20,000 Youngsters Finds the Naturally Left-Handed y ' as Efficient as the Right-Handed if They Are Not Forced to t Use Their Right Hands How the "Handedness of Everyone Is Shown at Birth by Bones T ' of One Hand and Arm Being Larger Than Those ct , 1 J of the Other Hand and Arm . U7. Franklin Jones, Ph.D. (Dead of the Department of Education and Director of the Graduate School, University Uni-versity of South Dakota.) SJ0ai NE of the most stubborn f vr i)rob'ems tnat evor cou" "if f fronted the educator is TV H B the Problem of handed- A ffL ness. One group of L fi theorists tells us that fflCCf left-handedness is just "individual habit," and that every child who reveals this, "unfortunate "unfortu-nate trait" should be "broken of the habit" and made to adopt his right hand. Another group tells us that left-handedness is a " deep-seated trait" and that we should "not interfere with nature in her process of hands." Still another group tells us that "two equal arms" should be the aim of all hand training, and ambidexterity is heralded her-alded as the solution of the problem. Xow, all these conflicting theories mean just one thing, and that is that we have heretofore lacked concrete evidence on which to base a theory of handedness. Before Be-fore we could settle the handedness controversy con-troversy we bad to push concrete investigation investiga-tion far enough to give us scientific measures meas-ures that enabled us definitely to distinguish distin-guish born handedness and adopted handed-ji'ss. handed-ji'ss. y There are three groups: First, pure S right-handers, individuals who are right-(Lhanded right-(Lhanded both by birth and by adoption; sec-cNv sec-cNv pure left-handers, individuals left-handed left-handed both by birth and by adoption, and, third, transfers, individuals born right or left and who have shifted to the other arm. We can make with these groups such tests for hand and arm skill as may enable us to pay whether or not the left-hander should be transferred or made over into a righthander. right-hander. It is this double problem that I have been working on for nearly ten years. In attacking the tirst problem that of devising devis-ing standards of measure I proceeded on the assumption that if the individual either is born with or has acquired unequal potentialities poten-tialities on the two sides of the body there must be some evidence revealed bv the tape line, as well as by weighing and sensibility tests. I therefore set out to measnre the paired bones and paired muscles not only of the arms but of all convenient part of the body, using cadavers as well as living beings. I soon found differences in the measures of the two sides of the body that seemed to indicate born handedness in one case and adopted handedness in another. Since my subsequent measures of 20,000 ' pairs of arms have justified this hypothesis, can now offer these standards as a part of my results: The right-hander is born with larger bones on the right side of the body, and the left-hander is born with a. similar development in favor of the left side. Hence we may speak of major and of minor arms, meaning that there is a larger -ijopment of one side and a minor development devel-opment of the other. Bone measures may reveal the birthright of hands, but the use, the adoption, of hands can be revealed only by the muscles. The muscle which is called into use more than others soon comes to F have a larger power and a larger muscle !f swell, and the comparative muscle swells of the paired muscles of the arms readily indicate the choice of hands and arms. Out i of many possible measures I have found the I following two simple groups to be reliable J means of distinguishing born handedness 1 1 and adopted handedness ; BORN HANDEDNESS. (The major arm exceeds the minor arm in these measures.) i 1. Length of the ulna plus, the large bone in the fororam, from the hand to the middle knuckle of the little linger. 2. Circumference of the palm. 3. Circumference of the wrist. 4. Length of the humerus, the bone ia the upper arm. ADOPTED HANDEDNESS. (The adopted arm excels in the muscle swell in these.) 1. Relaxed forearm circumference. 2. Contracted forearm circumference. : 3. Ketaxed arm (biceps) circumference. 4. Contracted arm (biceps) circumference. circumfer-ence. If the reader would like a little first- hand knowledge of the primary facts of , .X.lideduess he may easily derive the same by taking the measures of a number of 7 pairs of arms. Before he has measured a hundred he may catch a glimpse of the first great fact of handedness, already mentioned namely, that a human being is mightier on one side of the body than on the other. He will find about twenty-four out of twenty-five twenty-five individuals more massive on the right side. . If now the investigator will go a little further and compare the bone measures of a day-old child with similar measures of individuals in-dividuals 10, 20. 30. 40, SO, 60 and 70 years old he may readily compute the fact that right orleft handedness is just as findable in the child at the moment of birth as it is on any subsequent day of his life. . The child Is born right or left handed. Caution is here given that it is not safe to rely on the child's own choice of hands, . for the reason that the child may receive an injury to his major arm early in life that will cause him to transfer to the minor arm, and this, too, without the knowledge of parent or guardian. We have thousands of born right-handers who are today proceeding on the settled belief that they were born left-handed, simply because be-cause they have adopted the left hand through early accident to the right hand or arm, and we also have hundreds of born left-handers who are passing for born right-handers for. a similar reason. (See summary of 10,000 braehiometer tests that follows.) i Dangerous to Tie tJp Arm. It is a dangerous thing to place an arm J In a sfmg until we know whether or not it 6 is the major arm. The children shown in t the pictures are born right-handers who 1 have accidentally been transferred to the left arm The little girl in the middle picture, whose right arm Is 'being measured, was transferred by a "cracked" collar bone at 4 years of age. The right arm was never placed in a sling, but the child found she . could not use it without pain and she began using the left. She is now 6 years of age and has started to school. She Is being shifted back to the light arm in consequence con-sequence of brachiometric measures. I cite an instance which typifies the revelations unearthed in my research work : The individual was a girl 20 years of age who when measured was proved to be a lefthander, left-hander, -although she used her right hand exclusively In writing. In her case the ulna plus, the hone in the left forearm, measured 14 15-16 inches, w-hile In the right it measured but 14 12-16 inches. The right wrist was 6 inches: the left 6 2-16 inches. The right palm 7 4-10 Inches ; the left 7 6-16 inches. The right humerus 12 15-16 inches; the left 131-16 inches. A strange contradiction seemed to take place when I measured her forearm muscles, mus-cles, for the right arm had a great advantage advan-tage over the left. The right forearm relaxed re-laxed was 8 8-16 inches; the left 8 6-16 inches. The right forearm contracted was 8 12-36 Inches; the left S S-16 inches. The right muscles could swell 3 per cent, while the left made but 1.5 per cent. The first of these measurements Indicated Indi-cated beyond question that the girl was naturally left-handed ; the last tabulations declared that she was right-handed. Summary of 10,000. This system of measurements I have applied ap-plied to over 20.000 individuals, ranging in age from the infant to the centenarian. The summary of the first 10,000 of these measurements follows: OUT OF 10,090 PERSONS Only 417 re born left-handed. Four per cent of the race are left-handed; left-handed; 96 per cent are right-handed Out of 417 born left-handers 32: shift to the right hand. Seventy-seTen per cent o born left-handers adopt the minor arm. Out of 417 born left-handers foul are shifted by accident; 319 ar shifted by purposive interference; ninety-four are allowed to use th left arm. Out of 9,853 bora right-hander! ninety-six are shifted to the left ban (1 per cent, accident). Four hundred and nineteen per sons (323 plus 93) out of 10,000 adop the wrong arm that is, one persoi out of twenty-five is using the mino: arm. The significant conclusion drawn fron the foregoing data Is that the four bon measures as civen reveal burp handedness and the muscle measures as given reveal re-veal adopted handedness. Proceeding on the basis of this conclusion, it is an easy matter to measure and classify individuals in-dividuals into the three groups: First, pure right-handers; second, pure lefthanders; left-handers; third, transfers. jt I have taken 150 S-year-old children, seventy-five of each sex and twenty- five of each of the three classes, right- 5 ' handed, left-handed and transferred, jp and submitted them to the tests for t:i:::::iliilistS:ii : l : in ssMsSf m vfif - - - - Ill , - Professor Jones measuring the humerus hu-merus (long arm bone) of a child. skill named below. The tests were repeated on a similar number of 10, 12, 15 and IS year olds, respectively, similarly divided (half of each sex and twenty-five of each class of handedness). The skill tests applied ap-plied were the following : 1. Eate of tapping (number of taps with pencil in given time). 2. Placing wooden pegs in order in a peg board. 3. Threading the needle, with bristle substituted sub-stituted for thread. 4. Thrusting at a target with a three-foot three-foot wooden pointer. 5. Loading a glass upright tube with buckshot. The results follow: DEXTRALITY IN TAPPING RATE- (The records indicate the number of taps made with pencil in thirty seconds.) BOYS. Rieht Left Age. hand. hand.Tot!. Rijjht-handers 8 M8 M15 253 Left-handers 8 US 143 262 1 Transfers 8 130 136 2SS Right-handers 10 159 123 258 Left-handers 10 132 153 2S5 Transfers 10 133 142 230 Right-handers 12 13S 14R 310 Left-handers 12 149 168 317 Transfers 12 135 151 355 Right-handers 15 190 170 3C9 I Left-handers 15 173 182 355 Transfers 15 178 171 349 , Right-handers 18 195 182 377 Left-handers 18 1SS 193 379 Transfers 18 18S 183 338 ' GIRLS. 1 Right Left i Age. hand. hand.Total. 1 Right-handers 8 140 1 15 255 Left-handers 8 118 132 230 Transfers 8 120 123 243 ' Right-handers 10 153 126 22 i Left-handers 10 126 153 279 Transfers 10 135 144 2S0 Right-handers 12 167 140 307 Left-handers 12 142 153 305 1 Transfers 12 153 144 30S i Right-handers 15 ISO 131 311 r Left-handers 15 165 178 3(3 Transfers 15 171 169 3(0 Right-handers 18 191 167 35S a Left-handers 18 164 134 353 e Transfers 18 179 175 354 JVie records here given are the avcnnjcs f illl I $ S L . V W6L E3 B y Tests of ) MSldM landed y -f T$ ai 1H Forced to rf- '. LflliO I --, , C t? , r ' 1 T , ; V x v i -j ' r & j,f v i I I'Uainf. ' -i! w-i-" , s4'v v-'3c":Ht IBSSilills ' (Above), a "transfer," or naturallv right-handed right-handed hoy, using left hand r,t pencil-tappin? pencil-tappin? test, which shows the evil of transferring hands. - TTT -TrH? :::::::::::-:-::::-i:;E-E::--?'i.-iS : jjtf V'iiW-Vm i.Xit t-;s::?;:;s.i; mMm -i-M: mii'iiM a;.-: : : ' - f: -iiiJmmm k :;:JiM5:;i:i:.? -. : i mim-mm i-i!'?:; --.-: fete f .i'i WiS--.mr,m i . , K'- ' .-J B ?J" 5 ;y:S 5".'' B N- , Professor Jcnes using the brachiometer on the hand and Icver arm of a boy to determine if the chil'a is naturally left or right handed. per (roups of liecnlji-five children. The transfers mere all left to right. The most striking fact revealed is the low grade of skill shown by the transfers. While the average skill of the two hands of the transfers is not far different from il.o average skill of the two hands of either right. or left banders, in nut a single case does the tra nsferred group show the ext rcme skill with cither hand that the other two groups show. The transfer may hardly i.e said to nave a dextra! hand my arai, but rather two minor arms. He could hardly h.'pe to cumete with the pure right or left banders in this day of skilled labor, for skilled :abor more and more calls for one arm "f extreme skill. The so-called "ambidexter" "ambi-dexter" is the im'.ividual with two minnr aruis, fur lie is partially shifted from his born majnr ann to his born minor arm. He has failed to develop the potentially major .arm. "While he may have two reasonab'y go'jd arms, he does not have the extreme skill in one arm which he might have had. and he has been crippled in the field of skilled labor. The parent or teacher who assumes to make the left-handed child write with or otherwise adopt the right hand must assume the responsibility for making mak-ing that child a transfer in so far as the endeavor succeeds. It may "look-awkward" "look-awkward" for the child to use his left hand, but this is only evidence of a bad tradition. The left-hander may have to pay a little more for left-handed left-handed tools, but this, again, is only more evidence of a bad tradition. Penmanship Pen-manship teachers may still be unwilling un-willing to train left-handed writers (the author was once a penmanship teacher ami shifted all lef t-haadcrs). but that will be only a continuance of a bad tradition. There is but one thing to do with the born left-hander, and that is to see that he uses his left hand and arm. So long as the transfer Is close to what we may call the ambidextral Hue (the line i t cou:. liiy ol muscle swell of the two arms) it is not hard to return the transfer to his birihright in so far as .the arms tire concert, con-cert, ed. The moimnt we contemplate the effect in the reorganization of speceli-eentcr connections we feel that we should hesitate until we know more about the speech ranters. ran-ters. (The fact that I have found a large number of feeble-minded individuals and stutterers among the -liy transfers of my study easily causes me to f"ar any traaster from one jam to the other, but we need farther .studies here.) I have made a number num-ber of ret ransfers with children of pre-a'lolesient pre-a'lolesient age. and I did so on the assumption assump-tion that the neutral paths are not so estab- lished as to make it dangerous to unsettle them further. It is probable that we may safely retransfer any individual who has not passed puberty, provided the arm swells are not far from equal. I am unwilling to be dogmatic, and tho handling of the mature transfer must await further investigation. Our educational procedure, pro-cedure, however, is not at all doubtful, for we can and should make brachiometric measures of every child soon after birth and then make sure that neither accident nor purposive interference makes a transfer of him. Our problem of retransfer thus arises from the fact that we have permitted a transfer. Our standards of measure can easily discover the child's birthright. .(Copyright, 1917, by J. Kcclty.) Ancient Engines of War Hi-pHE mysterious British 'tank,' de-X de-X scribed as a car of death resembling a ponderous, slow-moving steel caterpillar. is the newest 'enfant terrible In the large family of strange engines of destruction sired by the God of War," says a bulletin Issued by the National Na-tional Geographic Society. "The modern lighting man has been so schooled to expect unique and powerful Inventions Inven-tions designed to destroy human life that the 'tanks' have inspired more curiosity than terror, but far different has been the story of the vast breed of monsters that have engendered panic in the hearts of soldiers in ages past. "One of the earliest engines en-gines of destruction whose fame has been perpetuated on the pages of legendary epic was the great wooden horse of Troy." The 300-foot towers on wheels and drawn by armored elephants were Cyrus' contribution contri-bution to the list of war engines. en-gines. These machines are pictured in the film drama "Intolerance." They reached to (lie top of the wall of Mabvlon and enabled Cvrns' men to drop bridges upon the walls and fight Holshazzar's men hand to hand. "Klephants." the geographic bulletin resumes, re-sumes, "were used again" and this is the first historic reference to them in war -"by I'yrrhus, Alexander's cousin, in the first of the famous 'Pyrrhic victories' over the Itomans. "Greek fire Is a term which has been applied to various compounds through a succession of centuries going as far back an 421 B. ('., when at the siege of Delium a cauldron filled with sulphur, pitch and charcoal was placed against the walls of the city, ignited aud the flames Intensified ,v- a bellows attached to a hollow tree trunk. The most famous of the Greek fires, however, was that h-von!el by the architect ('allinlcus during the reign of C'onslantine I'ogonHlus. This particular engine of destruction de-struction was known as wet tire on account of its property of bursting Into flame when wetted. Thrown from siphons. It fell uron sbins of the foe and saved Constantinople." |