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spirit in a hospital, like a happy spirit in a ship, isnot something which can be left to take care of itself.It has to be created, and two people are particularlyconcerned in this artistic act-the superintendent andthe matron. Staffing difficulties are worst wherethese fail in their task. The happy hospital, on theother hand, is its own recruiting officer, becoming ina literal sense a family affair : sisters, cousins, brothers,and wives, are enticed into the family party, andbring their own contribution to the imponderablesthat make for good work.

1. Pearce, R. A. H. Arch. Dis. Childh. 1953, 28, 247.2. McFie, J. J. Neurol. Psychiat. 1952, 15, 194.

Sinister v. DexterMAN is a lopsided creature. The skill of his masterly

hand and the subtleties of his commanding voice arecrowded, it seems, into one half of his brain, the leftor the right, according to his dominant laterality.The lateral dominance of man is usually regarded asinnate and complete : the assumption is that

" Nature always does contriveThat every boy and every gal,That’s born into the world alive,Is either a little Liberal,Or else a little Conservative ! "

But strict dichotomies, whether in politics or in

neurophysiology, tend to fail in the end for disregardof the undifferentiated middle. It now appears thatlateral dominance is a case in point.PEARCE has investigated the lateral preferences in

a sample of healthy school-children. He studied the

preferences between the four major paired organs :the ear, the eye, the hand, and the leg. His tests,which are attractively simple, are concerned essen-tially with lateral preference in voluntary motor acts.Thus, when testing eyedness, he regards as thedominant organ the eye used to spy through a telescopeor to sight through a hole in a card. (Tests used byother workers,2 such as the Phi test or Jastrow’s

ambiguous figure, do not depend on the voluntarychoice of one of a pair of organs, and the results ofthese tests may reflect different cerebral mechanisms.)The most striking finding was that nearly half of thewhole group showed some evidence of incomplete orconfused laterality. Complete right-sided dominancefor ear, eye, hand, and leg was found in 49-3% ; 4%were wholly left-sided ; and in 46-7% one or moreorgans were out of step. This surprising observation isimportant for three reasons : (1) if crossed lateralityis so common, then it is dangerous to regard crossingas the sole cause of any specific syndrome such asstuttering or dyslexia ; (2) the high prevalence ofnaturally crossed persons in the general populationaffects significantly the interpretation of studies ofunilateral parietal lesions ; and (3) such a large degreeof inconsistency suggests that the neurophysiologicalstatus of the term " dominance " should be reviewed.In parallel with his studies on laterality, PEARCE

considered the prevalence and nature of schoolingdifficulties in the same group of children. He foundthat 40% of the whole group had schooling problems,and that 70% of these problem children had somedegree of crossed laterality. Of the known crossed-laterals, only 15% escaped schooling difficulties. Thetype of crossing most commonly associated with

symptoms was that of hand and eye : this is to be

expected, since the finer motor skills are largelyproblems in eye-hand coordination. The overt

symptoms shown by the children were often quite farremoved from the underlying disability ; inattention,emotional disturbance, or a sudden obstinate refusalto learn were the common danger-signals. PEARCEshows that, under both natural and experimentalconditions, there is a basic symptom of crossed

laterality-namely, the reversal of units in a series.Such reversal, which is both unconscious and repeti-tive, may occur when the child scans-a series of lettersforming a word : the resulting neologism is often

unpronounceable and meaningless, and the child thenbecomes confused both about the sense of what he hasread and about the act of reading itself. The reversalof units seems to be limited to scanning of horizontalseries, for when a misread word is rearranged verticallyit is read without difficulty. Thus the word"LANCET" might be read as "LANECT," withresulting distress ; if the letters are rearrangedvertically the word is at once recognised. Themechanism of reversals in scanning a horizontal seriesis explained by PEARCE as follows :When a left-eyed child scans a line of print the eyes

enforcedly swing from left to right; but, now and then,the eyes will make little hops backwards to the left, andthese hops coincide with the reversals. The hops representthe innate tendency of sinistrals to scan from right to left.PEARCE finds that the course of crossed lateralitydepends on the intelligence of the child. The highlyintelligent rapidly compensate, but children withmoderate intelligence, and those whose symptoms havebecome linked with emotional distress, need activehelp. He has developed ingenious methods of treat-ment. Essentially these consist in linking two modesof perception to each unit. Thus numerals are associ-ated with musical notes in a rising scale ; and printedletters are apprehended both kinaesthetically and

visually by training the child to trace each letterwith a finger while scanning it with his eye. Similarlyan emphatic rhythm is found to aid the sequence ofverbal memory. Anyone can confirm this by recitingthe alphabet backwards, first in a monotone and thenin the jingling trochees of the nursery-rhyme : ZYXand WV, UTS and RQP.

PEARCE discusses the setioiogy of crossed laterality,and having found a familial tendency he deducesa genetic origin. Genetic endowment is possibly afactor, but the known facts will not bear the weightof any precise genetic hypothesis.3 Perhaps the moststriking objection to any simple genetic hypothesis isthat monozygous twins are quite commonly of

opposed laterality. PEARCE asserts that if the domi-nant hemisphere is damaged in early life, then domi-nance and the control of speech may be transferredinto the naturally minor hemisphere. Similarly, hesupports the hypothesis that stammering after anenforced change in handedness is due to conflict indominance between the right and left hemispheres-a conflict which he compares with putting two menin the driving-seat of a coach-and-pair. This personifi-cation of dominance may be misleading. It is basedon the concept of the minor hemisphere as, so to

speak, the fetch, alter ego, or Doppelganger of itsdominant partner. But the work of ZANGWILL,4 and3. Gates, R. R. Human Genetics. London, 1946 ; vol. 2, p. 1162.4. Humphrey, M. E., Zangwill, O. Z. J. Neurol. Psychiat. 1952,

15, 184.

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of SUBIRANA,5 and their colleagues suggest that left-handedness implies that dominance has not simplybeen transferred to the right hemisphere, but ratherthat it is not fully established in either hemisphere.Sinistrality is thus not a positive quality but a lack ofdextrality ; and the fact that so many of PEARCE’S

left-eyed children showed crossed laterality tends tosupport this concept. The distinction between thetwo hypotheses is fundamental to human neuro-

physiology and turns upon what we mean by " domi-

nance." A parallel is found in theological conflict.The Manichean heresy asserted that man’s acts were

the product of conflict between the two opposed andequipotent concupiscences of good and evil; butST. AUGUSTINE, after personal experience of the practicalhorrors of that doctrine, countered with the dictum thatevil regarded sub specie œternitatis, had no positive qualitybut was a mere privation of the good.This analogy is less remote than it may seem ; forthere is, oddly, a semantic link between the theologicaland the neurophysiological problems. We use deriva-tives of the word " left " to imply evil, ambiguity,and acts outside the law, as in " sinister," " left-handed compliment," and the " bar sinister " of

illegitimacy ; while derivatives of " right "

suggestvirtue, accuracy, and honour as in " righteousness,"" dexterity," and "

uprightness." Moreover thedurable superstition of cheiromancy (which ARISTOTLEendorsed) distinguishes in the palmar grooves of theleft hand the ancestral pattern of a man’s character,and in the grooves of the right the impress of his ownwilled acts. The silent currents of superstitition andverbal habit may not be without influence in ourreflections on the nature of laterality.The basic failing in crossed laterals is an unconscious

reversal of units, scanned dextrad in a horizontalseries. This apparently specific sign is found also inorganic cerebral disease. Patients with anosognosiaderiving from a right parietal lesion may be able torecognise a word printed vertically but unable to

spell out the same word horizontally ; and peoplewith right homonymous hemianopia have beenobserved to turn their books through 90° in order toread vertically rather than horizontally. PEARCE’Smethod of teaching the dyslexic to trace the lettersout with a finger was described by WILBRAND as aspontaneous sign shown by " word-blind " patientswith organic cerebral disease, signifying their attemptsto read kinæsthetically rather than visually. The

practice of scanning print dextrad is not a physiolo-gical necessity but is, rather, a cultural practice.Semitic writings commonly run sinistrad ; some ofthe Celtic Ogham inscriptions run vertically upwards ;the cuneiform of ancient Mesopotamia, at first vertical,changed to horizontal about 3200 B.C. ; both the

hieroglyphic and the demotic scripts of Egypt werewritten sinistrad. Finally some early Latin andGreek inscriptions employ the remarkable boustro-phedon style,6 in which alternate lines flow right-to-left and left-to-right, the individual letters of thesinistrad lines being mirror images of their dex-trad counterparts ; this style is, incidentally, moreeconomical of eye movements than our own.Most of the great neurologists have pondered on

the problem of man’s curiously biased abilities ;

5. Subirana, A. Schweiz. Arch. Neurol. Psychiat. 1952, 69, 1.6. Critchley, M. Proc. R. Soc. Med. 1927, 20, 397.

SHERRINGTON and RUSSELL BRAIN 7 have compara.tively recently examined the fundamental problem, andMACDONALD CRITCHLE1;" s has investigated the neuro.pathology of lateral dominance with great subtletyand insight. Too much of our knowledge of lateralityhas come from the study of diseased adults ; large.scale longitudinal studies made, like those of GESELL,on healthy children are necessary before we can hopeto understand the natural lopsidedness of man.

7. Brain, W. R. Lancet, 1945, ii, 837.8. Critchley, M. The Parietal Lobes. London, 1953.9. Somerville, E. W. J. Bone Jt Surg. 1953, 35B, 568.

10. Scaglietti, O. Report on Congenital Dislocation of the Hip for4th Congress of the International Society of OrthopædicSurgery, Brussels, 1939.

11. Leveuf, J. Ibid.12. Schede, F. Ibid.13. Muller, G. M., Seddon, H. J. J. Bone Jt Surg. 1953, 35B, 342.

Congenital Dislocation of the HipTHERE is increasing dissatisfaction with the treat.

ment of congenital dislocation of the hip. The generalimpression is that even with early closed reductionfollowed by skilled conservative treatment only a

small proportion of patients will pass the age of 30without trouble having started. On the other hand,untreated dislocation, particularly if bilateral, maycause surprisingly little disability, and the patientmay remain free from secondary troubles until theage of 50 or 60 ; this disorder does not shorten thenatural span of life. If the best we can offer is analmost normal hip until the age of 30, but thenincreasing trouble, there is good reason for concludingthat the standard we have accepted is too low.One difficulty in assessing the results of treatment

is that the cases do not form a homogeneous group,and we do not know how the dislocation occurs. Insome there is definite dysplasia which may be asso-

ciated with other congenital abnormalities ; herereturn to complete normality can scarcely be expected.DENIS BROWNE maintains that pressure from theuterine wall on the knee can force the femoral headbackwards out of its socket, and of course dislocationshave occasionally been demonstrated radiographicallyin utero. In other cases the dislocation apparentlytakes place after birth, and SOMERVILLE 9 suggeststhat the cause is the postnatal extension of a laterallyrotated hip with an anteverted neck. A second

difficulty in assessing results is that each surgeontreats only a limited number of cases, the follow-upperiod has to be very lengthy, and changing methodsmake assessment of the results by any one workeralmost impossible. In attempts to overcome this

difficulty cases from large centres have been reviewed-notably in 1939 by SCAGLIETTI, 10 by LEVEUF,11 andby SCHEDE.12 An outstanding contribution has nowbeen made by MULLER and SEDDON,13 who have madea most painstaking survey of cases treated at the

Royal National Orthopaedic Hospital.Their aim was ’’ to determine the fate of hips I

reduced by orthodox closed reduction as a basis forcomparison with the new regimen of

" closed reduction... and early operative intervention if reduction wasnot successful." Of the 889 recorded cases treatedbetween 1890 and 1940 they traced and examined264, but of these only 52 had been followed for morethan thirty years. They found that the factor ofheredity was less distinct than in the much largerItalian series of ScAGLiETTi; nevertheless they