724 THE STUDENT AT THE SCHOOL CLINIC.

was doubtful 852, while the deaths ascribed to cow-poxand other effects of vaccination were 22. Hero we

may be grateful for quite a good instance of the needfor precautions in the use of statistics. Incomparableitems must not be compared ; when comparing itemswhich appear comparable, it is necessary to ascertainwhether other factors affecting the result, besides theone under comparison, have varied substantiallyduring the same period. There are such phenomena asepidemic waves; there is such a thing as an " epidemicconstitution " determining, though we do not knowhow, the intermittent prevalence to an abnormalextent of small-pox, diphtheria, or scarlet fever. In

estimating the value of any therapeutic or prophylacticmeasure we must know the proportion of attacked tokilled in comparable groups, and the number notattacked to the number attacked in similar comparablegroups. The habit of mind which appreciates thesethings is one of the objects of a liberal medical educa-tion. So much is desirable in order to interpretrightly the work of others and not to be misled byfaulty interpretation. The Registrar-General has setan example by warning us not to read more into hisfigures than they will carry. They can tell no morethan is embodied in the certifying practitioners’returns, and as these become more accurate hisdeductions from them will grow in value.

THE APERIENT WATERS OF ESSEX.

THE county of Essex lies for the most part in abasin of London clay, the strata of which in someplaces are almost friable from the presence of calciumsulphate. Sulphated water is abundant all over thecounty, and it is a frequent experience for the countyauthority to receive for analysis a sample of watertrom a newly sunk well and to issue a report in theform : " Useless for drinking purposes ; may beuseful as a mild aperient." The water from a wellat Vange, to the properties of which some publicityhas been given, resembles closely that of the neigh-bouring well at Hockley, described ten years ago byMr. Miller Christy, F.L.S., and Miss May Thresh in aHistory of the Mineral Waters of Essex, contributedto the Essex Field Club Memoirs. The well atTilbury, which is still nearer, was at one time famous,but has passed completely into oblivion. There areelsewhere in England numerous weak sulphatedsprings now disused, of which Epsom, Beulah Spanear Norwood, and Purton near Swindon at one timepossessed considerable reputation. Nowhere in thiscountry do we possess the concentrated sulphatedsprings, such as that of Marienbad, which containsnearly 5 per cent. of Na2SO4, or that of Robinat inSpain, which contains 10 to 12 per cent. These strongwaters are not drunk at the source, but are bottled

Ifor distribution as medicinal purgative doses. TheLeamington sulphated water contains 1-2 per cent.of Na2S04 and 0-9 per cent. of MgS04; the Chel-tenham spring has nearly double the sodium contentand one-third of the magnesium. The reputation ofalkaline aperient waters in disorders of metabolism islargely based upon the assertion of Seegen thatingestion of small doses of sulphate of soda diminishedthe disintegration of nitrogenous substances while itincreased the combustion of fat; although hismethods came under criticism, his conclusions receivedsupport from later observers such as Jacques Mayerand Loewy. Dr. Matthew Hay attributed the

action of saline purgatives to a true increased secretionin the intestine, due not to osmosis but to the irritantand specific properties of the salt and also probably toits bitterness. Whatever the practical value of thewaters, the popularity of such alkaline purgative spashas been ephemeral in this country. A pump-roomwas built at the Hockley Spa in 1842, but the enter-prise was not a success, for in 1871 the hotel had becomea beer-shop and the spa room was in use as a chapel.

Annotations.

THE STUDENT AT THE SCHOOL CLINIC.

"No qnid nimis. "

j N reviewing some reports of school medical oflicers notlong ago we commented on the fact that no advantageappeared to be taken by the large university towns ofthe enormous fields opened for instruction of studentsby the medical inspection and treatment of school-children. The dental department of Liverpool Univer-sity, discovering with alarm that the appointmentof school dentists on a large scale would deprivethe University of an extensive portion of itsclinical material, has now come to an arrangementwith the Education Committee, whereby theUniversity’s final-year dental students have toput in at least three months’ work at a school clinicunder the supervision of the school dentist andthe dental teaching staff of the University. Thearrangement carries advantages for both the Univer-sity and the local authority, and the child does notsuffer, as the work is supervised as strictly as at thedental hospital, where until now the children have beentreated. It is to be hoped that this cooperationbetween the teaching staff of a university and thestaff of the school medical services will be extended tocover other grounds. The study of the normal andabnormal child together makes for a much morethoroughly considered and balanced judgment thanthe continuous study of the abnormal, and thiscooperation would do away with the lack of sympathythat too often exists between the hospitals and theschool doctor. Apart from the field of research opento him, the student would learn much that would beuseful to him afterwards, if at first only how todiagnose ringworm. Every school doctor has comeacross cases of definite ringworm dragged by wearymothers from one doctor or institution to anotherand turned away from each with the assurance thatthe case is not one of ringworm. Many authoritieshave even found that the only way to reduce thenumbers of ringworm cases is to accept only the schooldoctor’s certificate of cure. Dr. E. W. Hope dis-covered that by this proceeding he was able toreduce the number of these cases in Liverpool from1400 in 1911 to 950 in 1912. The figure now isbetween five and six hundred. Certain sociologicalaspects of medicine would also be brought prominentlybefore the student who attended school clinics as partof his training in paediatrics.A special investigation into the cause of school

absence, for example, was recently undertaken inLiverpool, the results corresponding closely enoughto those found elsewhere. Five-sixths of the totalabsences were due to medical reasons. The periodchosen for investigation was the first quarter of theyear, when school attendance is usually lowest. Fourschools in fairly good neighbourhoods were comparedwith four in a poorer district. Respiratory troublesaccounted for the largest number of absences, next cameinfectious disease, and then high on the list came skinaffection. The majority of diseases ran almost parallelin both districts with the exception of eye affections,which are four times more common in the poorerschools, and skin diseases which are twice as common.Respiratory troubles as well as general debility andanaemia in the better-class schools are twice as

common as in the poorer, indicating probably agreater amount of precaution or coddling on thepart of the better-class mother. Girls, too, showmore tendency to be kept at home than boys, andinfants, as would be expected, most of all. Thelarge amount of eye affection in the poorer schoolsis significant, and is attributed by Dr. Hope to thepoor nutrition and the want of cleanliness of thechildren, most of the trouble being due to blepharitis.It was found, too, that 36 per cent. of the children inthis city were not wearing their glasses. This meansthat much more than half the cases of hypertropia

725

do not use the glasses prescribed, as children make aspecial effort to have their glasses at the doctor’s visit.Over 100 out of close on five times that number ofchildren suffering from pulmonary tuberculosis werein institutions, where classes have been arranged forthem. The resident doctor emphasises the therapeuticvalue of such mental stimulus in this disease. Duringthe year 43,469 children under the code group wereeexamined and 7109 referred for treatment. During thesummer holidays games for children remaining in thecity were organised, and paid supervisors took chargein five of the most frequented parks. Storage huts forapparatus were provided in each of them. Voluntaryhelp came forward in the shape of parents, universitystudents, and onlookers, and in the five parks there wasan average daily attendance of 996 boys and girls inthe mornings and 3334 in the afternoons.Those who draw up the curriculum may contend

that it is impossible to demand more time forpaediatrics or sociological medicine from the under-graduate, but the substitution of certain school clinicattendances for those of the out-patient departmentmay prove a valuable means of interesting him in thewider aspects of preventive medicine.

A CLINICAL THERMOMETER IMPACTED INTHE DUODENUM.

Dr. G. A. Preis, of Zurich, reports 1 a case of impactionof a clinical thermometer in the duodenum. Thepatient, a girl of 21 years, had previously sufferedwith pelvic inflammation and arthritis of the knee ofgonococcal origin, and owing to mental excitement andsuicidal tendencies she had on several occasions beenunder observation in a mental institution. In June,1920, she was admitted into the surgical clinic withthe diagnosis of acute appendicitis, complaining ofright-sided abdominal pain and frequent vomitingof several days’ duration. She complained also ofpain in the right renal region, but the physical signsand examination of the urine excluded pyelitis. Theappendix was removed on the same day, and presentedsmall punctiform haemorrhages in an otherwise normalmucosa. There was no peritoneal exudate, and thepelvic organs were normal on palpation. The woundhealed by first intention, but the pain persisted andthe temperature remained slightly above the normal.The pain increased in severity, and later vomitingstarted again. About three weeks after admissionthe pain was localised to the epigastrium, and slighttenderness to the right of the middle line was found,vomiting became more frequent, and the patientbegan to look ill. She was now questioned morethoroughly as to the onset of the disease, and ittranspired that ten weeks previously, while in anasylum after an attempt at suicide, she had swalloweda clinical thermometer, and that this had never beenrecovered. On this story being obtained X rayexamination was undertaken. A screen examinationrevealed a fine straight shadow simulating a needle,and on further accommodation a clear zone could bemade out surrounding it, and the form of a thermo-meter could be clearly demonstrated. It lay on theright transverse processes reaching from the twelfthrib above to the level of the fifth lumbar vertebrabelow. A barium meal confirmed the screen appear-ances. The first part of the duodenum was tent-shaped over the top of the thermometer, while thesecond part was thinned out and lengthened. Aperforation was excluded by the smooth and rapidpassage of the barium along the intestine. The sameday operation was undertaken. The peritoneumwas divided over the duodenum, and the thermometerwas clearly palpable in the position revealed by theX rays. No inflammatory changes in the peritoneumor periduodenal tissues were present. The duodenumwas opened and the thermometer extracted entire.The duodenum was closed in three layers and theabdominal wall sutured. Recovery was uneventful,and the patient was discharged free of symptoms.

1 Medizinische Klinik, August 27th, 1922.

The patient stated that the nurse had shaken thethermometer down and placed it in the axilla, and thatshortly afterwards she had removed it and swallowedit. On removal it registered 41-5° C., and this readingis interpreted by Dr. Preis as a record of the highesttemperature of the interior of the duodenum. Herefers to the experiments of Ito, who showed that indogs the duodenal temperature was only 07° C. higherthan the rectal, and that a rise to 41.5° C. wasimpossible. The only explanation acceptable toDr. Preis was that the phenomenon was due to theingestion of hot fluids, which may leave the stomachvery rapidly. It does not seem to have occurred tohim that a patient sufficiently unstable to remove aclinical thermometer from her axilla and swallow itmight be familiar with the many well-known devicesfor the artificial production of a high reading.

THE TSETSE-FLY.

THE tsetse-fly, or Glossina, ill-famed as a dissemi-nator of trypanosomes, is confined to Africa, withthe exception of one species, which is also found inArabia. Nineteen species of Glossina are now

recognised, besides several additional races or varieties.Accurate descriptions of these flies, as far as knownup to the year 1911, were given in Major E. E. Austen’s" Handbook," and in an important mono.-raphl 1which has just appeared the following additionalspecies recognised since the appearance of that workare included: G. austeni Newst.; G. ziemanniGrunberg ; G. haningtoni Newst. and Evans ; G.severeni Newst. ; G. schwetzi Newst. and Evans.Fuscipes, maculata, and submorsitans are not regardedas valid species. The most important species of tsetse-fly are G. palpalis and-G. morsitans, which are ordinarilythe invertebrate hosts of Trypanosoma gambiense andT. rhodesiense respectively ; the latter organisms candevelop in G. brevipalpis also, and it is likely thatmany species of Glossina may be efficient hosts fortrypanosomes. As is well known, tsetse-flies do notlay eggs, the female producing a single mature larvaat a birth ; on extrusion the larva conceals itselfusually by burrowing into the soil, where it pupates.A very interesting account is given by Major Austen

and Mr. Hegh of the breeding habits of tsetse-flies.G. palpalis breeding places are shady, with dry loosesoil or dry vegetable débris. The sites chosen haveusually water in the vicinity, but breeding placeshave been found over 1600 yards from any discover-able water. Lloyd records G. morsitans breeding insuch places as hollows in trees, beneath fallen deadtrees or branches, or in burrows of animals, and pointsout that the one feature common to all the breedingplaces found was the presence of some relativelydark spot for the fly to conceal herself during gesta-tion. Most of the pupae were found in unmistakablerelationship to native and game paths, fords, drinkingplaces, and salt licks. A similar selection of thevicinity of game paths is recorded by Lamborn forG. brevipalpis. The authors record the experiences ofmany observers regarding the habitat of differentspecies of tsetse-flies, some divergence of opinionbeing expressed. Neave’s interesting classificationof East African Glossina according to environment isgiven :

A. Requiring a great degree of atmospheric humidity :—

(1) Requiring a high temperature-palpalis.(2) Not requiring a high temperature-fusca.

B. Requiring only a moderate degree of humidity :—

(1) Requiring comparatively little cover-pallidipes.(2) Requiring fairly heavy timber and bush-brevipalpis.(3) Requiring more or less dense forest-austeni.

C. Independent of water and most active in a dry atmos-phere-morsilans and longipennis.The food of tsetse-flies and their relation to big

game is carefully gone into. The question of thedependence of Glossina, especially G. morsitans, on

1 Tsetse-Flies, their Characteristics, Distribution, andBionomics, with Some Account of Possible Methods of theirControl. By Major E. E. Austen, D.S.O., and Emile Hegh.Pp. 188. 7s. 6d. Imperial Bureau of Entomology, 41, Queen’sGate, London, S.W. 7.