649A YFAR’S ATMOSPHERIC POLLUTION.

present number, contains evidence of the large amountof painstaking care which is being devoted to theairman’s health. The report contains many tablesinvolving accurate and minute records. Nosologicalclassification is, indeed, carried so far as to have

hardly more than provisional value for the numbersreached in a twelvemonth, but the statistician ten yearshence will have an enviable opportunity of computingsickness rates on a new class of material. The troublewith all such analyses is to ensure sufficient accuracyin recording the observations on which the figures arefounded and to avoid wasting time classifying them.In this case a highly ingenious system of mechanicalsorting has been adopted in which, once the materialhas been transferred to certain cards, they are availableat any future date for special investigation in respectof a particular period. The clerical labour saved bypunching holes in code cards and leaving a countingmachine to do the rest must be seen to be realised.

Study of the incidence of disease and injury among thevarious occupations in the Air Force has already giveninteresting results, which will lead in their turn tonew lines for future examination. The groups of

carpenters, riggers, drivers, fitters, metal workers,and other skilled trades all show a disease rate abovethat for the total force, rising in the case of certainspecialised workers to 637 per 1000 of average annualtrade strength, against 410 per 1000 of aircraft hands.The proportion of disease to injury in the Air Force isnotably higher abroad (7 : 1) than at home (6 : 1),and the factors concerned in this difference are

interestingly set forth in the report. In home

squadrons the proportion of disease to injury sinks aslow as 3 to 1, the risk inherent in flying being increasedby propeller and starting-car accidents as well asthose of skilled trades. The report itself may bestudied with interest as a bold attempt to face anovel situation with the added physiological equip-ment of the time.

A COMBINED APPEAL FOR THE HOSPITALS

OF LONDON.

King Edward’s Hospital Fund for London hasundertaken the organisation of an appeal on behalf ofthe voluntary hospitals of London, with the aid ofthe Hospital Saturday Fund, the Joint Council ofthe Order of St. John and the British Red CrossSociety, the League of Mercy, the London RegionalCommittee of the British Hospitals Association,the Metropolitan Hospital Sunday Fund, and thehospitals themselves. His Royal Highness the Princeof Wales has approved of his name, as President ofthe King’s Fund, being used in connexion with theappeal. An organising committee has been set up,under the chairmanship of Sir Alan Anderson, K.B.E.,(chairman of the Revenue Committee of the King’sFund); Sir George Lawson Johnston, K.B.E.(member of Council of King’s Fund), is chairman ofthe Executive Committee, with Mr. E. S. Shrapnell-Smith, C.B.E., as Director-General of the AppealCampaign, and Captain E. J. C. Chapman, M.C., ashis deputy. Offices have been secured at 19, Berkeley-street, W. 1, to which address all communicationsrelating to the appeal should be sent.

LITERARY INTELLIGENCE.-The Oxford University ’’

Press announre among their new and forthcoming books :" Csreek Biology and Medicine " and " Medieval Science,"by Dr. Charles Singer (Clarendon Press): ’’ The Evolutionof Modern Medicine," by Sir William Osler, and " Respira-tion," bv Prof. J. S. Haldane ’’for the Yale fTniversit’T Press).—Messrs. W. Heffer and Sons, Ltd., announce the publica-tion of " Fundamentals of Bio-Chemistry in Relation toHuman Physiology," by T. R. Parsons, B.Sc., M.A.,Demonstrator in Physiology in the University of Cambridge.

Annotations.

A YEAR’S ATMOSPHERIC POLLUTION.

"Ne quid nimis."

’1’Hr seventh report 1 of the (Jommittee for the3 Investigation of Atmospheric Pollution covers the7year ending March 31st, 1921, when 31 stations were> in operation for measuring deposited impurity. The-

returns from these showed the mean monthly depositi of impurities to range from 24-85 metric tons perI sq. km. to 4-22 in Rothamsted. London occupies an’ intermediate position with between 11 and 12 metricJ tons per sq. km. These figures multiplied by 2-56j give values in English tons per sq. mile. Where, comparisons were possible with the winter of 1920--21: the deposit was less than in the previous winter in,

] 9 cases and greater in 4, the increase in no case. exceeding 7 per cent. On the other hand, there was a,

fairly general increase--chiefly of tarry matter-inthe summer deposit of 1920 as compared with the

: previous summer, the Meteorological Office gauge.

showing a plus of 100 per cent. Mr. J. R. Ashworth,1).Sc., describes an attempt made to measure Rochdale’sresponsibility for its own atmospheric pollution. Thegross amount of deposit brought by the west windsinto the town from external smoke-laden areas wasfound to amount to no more than 19 per cent. of thetotal received in the central gauge, and when this isallowed for Rochdale still maintains its pre-eminencefor pollution over other town’s of its size and popula-tion. This interesting problem might be applied toother cities. Birmingham (Central) heads the listfor insoluble carbonaceous matter and ash, Newcastlecoming next. The highest deposit of tar was in theMeteorological Office gauge, London, the secondhighest again being Newcastle. Liverpool showed thehighest deposit of soluble matter, Glasgow the secondhighest along with the highest ammonia. In fourcases Rothamsted, which is an open agriculturaldistrict, showed the lowest or second lowest deposit ;Birmingham (South-Western) also ranks lowest, or

second lowest, for four of the elements of pollution;Southport (Hesketh Park) is lowest or second lowestin five instances; and London gauges give the lowestdeposits in five cases. It is curious to note in com-paring winter with summer that the summer depositfor all elements of pollution was the greater, with theexception of tar and sulphates, both of which areproducts of combustion.

Six automatic instruments were in operation formeasuring suspended impurity, and curves are showngiving the results obtained in London by means ofthe ingenious automatic instrument devised byDr. J. S. Owens. In these curves groups of foggy daysare plotted together and groups of days withoutabnormal fog. They go to show that London air ispurest between midnight and 6 A.M. On week-daysand Saturdays at about 6 A.M. or a little earlier, andon Sundays at about 7 A.M., a rapid increase in theamount of impurity begins. This continues until amaximum for the day is reached, on week-days andSaturdays about 10 A.M., and on Sundays between11 A.M. and noon. In all cases the quantity of sus-pended matter begins to fall off rapidly after thismaximum, which seldom lasts for an hour, but in theafternoon a second, but lower, maximum appears about4-5 P.M., continues until 8 P.M. or so, after which a rapiddrop from 10 P.M. till midnight brings the quantityagain to. the minimum. The amount of impuritypresent evidently bears a close relationship to humanactivities ; the most noticeable fact is the uniformitywith which the impurity commences to increase at thetime when fires are lighted in the morning and thealmost complete absence of impurity during the periodfrom midnight to 6 to 7 A.M., when both domesticand factory fires are out of operation. The peak

1 M.O. 249. H.M. Stationery Office. 2s.

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between 4 to 5 P.M. suggests a tea-time rise. Fromthe fact that the greatest quantity of impurity isfound in the forenoon, it may legitimately be inferredthat the main source of smoke impurities is from firesduring the process of attaining their full heat. Theratio of factory to domestic smoke in Westminster isabout 1 to 3-25, and the figures indicate clearly thepreponderating effect of domestic fires in causingpollution of the air, a fact strikingly confirmed by thedense fog of .Tan. 22nd, 1922, which occurred on aSunday when domestic fires must have been prac-tically the only source of smoke. An attempt has beenmade in the report to correlate the number of deathsoccurring in London during the last quarter of 1920with the amount of suspended impurity in the air,which might with advantage be followed up. Finally, Ia special note is included by Dr. Owens upon fognuclei, in which it is stated that the diameters of thesmoke particles causing London fogs vary between1/100,000th and 7 /20,OOOth of an inch. During aneast wind, when the fog extended as far as Cheam, inSurrey, about 12 miles out, particles of the same sizewere found in large numbers. The amount of sus-pended impurity in the air of London during winter.appears to be of the order of 1 mg. per c.m. duringthe day but may fall much below this on clear nights,between midnight and 6 A.M. During a dense fog theamount rises to about 5 rng. per c.m., and it isremarkable how small a quantity of impurity issufficient to bring about even a dense fog, doubtlessowing to the extremely small dimensions of theindividual particles. The amount of smoke producedduring four morning hours in London is held to besumcient to account for the total amount of sus-

pended impurity found during a smoke fog.The report confirms the view, already many times

set out in these columns, that urban air pollution isdue to unburned fuel from many sources and that acampaign for pure air must be a comprehensive one.

THE SOURCE OF "TONSILS AND ADENOIDS."

THE considerable part of the public who are alwaysopposed to

" the knife," and refuse to allow the removalof their children’s enlarged tonsils and adenoids, haswelcomed the publication of the similar views of amember of the medical profession. However, statisticalinformation is available showing the after-results ofoperations performed which deprives those suspiciousof the accepted surgical treatment of their bestargument. School medical officers have especialfacilities for seeing children after operations and obtain-ing valuable information regarding them, not onlyfrom the parents but also from the teachers. In theannual school medical report for Derbyshire for 1921Dr. Sidney Barwise reports that the after-history wasobtained in the case of 296 children operated on forthe removal of tonsils and adenoids ; 87 of them hadboth defective hearing and discharge from the earprior to operation ; when examined afterwards, inaddition to their hearing being improved the ears of53 were found to be dry and the discharge in the caseof 33 others less ; in 1 child only was improvementwholly lacking. Of 209 children with impaired hearing,the hearing became normal in 99 and improved

.

in 104 ; in 6 only did no improvement take place.Dr. Barwise also made inquiries of some 400 parentsto obtain their opinion as to the effect of the operationon their children. The replies showed that 75 per cent.of the children were hearing better, 91 per cent. werebreathing better, and that 70 per cent. suffered lessfrom repeated colds. Inquiries made of the teachersshowed that 79 per cent. of the children improved intheir general health and in 75 per cent. an improvementin intelligence occurred and the children becamecapable of a higher standard of educational work.The prevention of the condition should be one of theaims of public health work. Each of various causeshave their determined exponents. In the opinion ofsome the condition is consequent on lack of develop-ment of the maxilla ; others attribute the evil to

absorption of the products of nasal catarrh, and

l others still to carious teeth. Obviously careful inquiry; to obtain evidence on these points is both welcome andL opportune. On p. 663 of this issue will be found; a copy of the inquiry form to be used in Derbyshire; in connexion with school children. It would seem; desirable that similar inquiries should be made in; connexion with children below school age attending: infant welfare centres. Although the opportunities; for conducting the investigation are not so abundant, as in the case of children attending school, yet probably

sufficient data could be contributed by a group of such. centres ; valuable evidence might be forthcoming in: this way as to the earliest age in which the conditions

are present to any considerable extent.

PHYSIOLOGY OF THE GALL-BLADDER.

Meltzer found that when magnesium sulphate wasapplied to Vater’s ampulla at the opening of thecommon bile-duct into the duodenum, bile was

discharged into the gut. He believed that this wasdue to relaxation of the sphincter, accompanied, inaccordance with the law of contrary innervation, bya contraction of the gall-bladder. On this observa-tion Lyon" based his technique for the testing ofgall-bladder function, and for medical bile-drainage,now so extensively used in America. The techniqueconsists in the introduction into the duodenum ofconcentrated magnesium sulphate solution andsubsequent withdrawal at intervals of duodenalcontents for chemical, histological, and bacteriologicalexamination, the assumption being that the secondaspiration consisted largely of gall-bladder bile.Much controversy has centred round this technique.Bassler, Luckett, and Lutz 2 observed the gall-bladderin men during operation, and saw neither a relaxationof the sphincter nor a contraction of the gall-bladderwhen magnesium sulphate was given by a duodenaltube. Accordingly, they doubt the value of thetechnique. Smithies, Karshner, and Oleson,3 on theother hand, defend it as useful in practice, and claimquite reasonably that observations made underanaesthesia cannot be regarded as final. L. S. Austerand B. B. Crohn 4 performed experiments on ants-thetised dogs, and in their experiments afterlaparotomy and duodenotomy the gall-bladder wasfound distended in all except one-a fasting animal-in which the bladder was seen to be flaccid. A solutionof methylene-blue was injected into the gall-bladder todifferentiate its content from the bile flowing from theliver. The duodenal mucosa in the region of andincluding the papilla of Vater was irrigated with mag-nesium sulphate solution. Although an increased flowof bile was observed, no expulsion of the gall-bladdercontent was noted. This observation was carried onfor several hours in eight dogs. The gall-bladderretained its bile independent of whether the dog was inthe fasting or the actively digesting state. Stimulationof liver bile flow, as obtained with magnesium sulphate,was also observed after the application of sodiumsulphate, sodium phosphate, peptone, N/10 hydro-chloric acid, peptone, bile and sodium glycocholate.No stimulation was seen after the application of water,sodium chloride, or sodium hydroxide. Attempts toproduce contraction by nervous stimulation were

unsuccessful, nor did direct faradic stimulation of theorgan produce contraction or expulsion of contents.

In another series of experiments phenoltetrachlor-phthalein was injected intravenously and sub-sequently recovered when excreted in the bile, andshowed the appearance of this substance in theduodenum in from 10 to 15 minutes after injection.A flow into the gall-bladder of liver bile was demon-strated by the recovery of the phenoltetrachlor-phthalein from the bladder bile when the cystic ductwas patent. None of the dye was found in the sacwhen the duct was tied. Observations on the fillingof gall-bladders emptied by digital compression showedthe filling to be a slow and irregular process, in spite1 Am. Jr. Med. Sci., 1920, clx., 515. 2 Ibid., 1921, clxii., 671.

3 Jour. Amer. Med. Assoc., 1921, lxxvii., 2036.4 Proc. Soc. for Expt. Biol. and Med., xix., No. 3, 1921.