180 BASAL METABOLISM IN THYROID DISEASE.

the optimum pH for an enzyme’s action may varyaccording to its degree of purity. Lipase in thehuman stomach, unlike pancreatic lipase, has itsoptimum action at pH 5-6 ; and the same is truefor the stomach of the dog. After purification humangastric lipase has its optimal activity in alkalinesolution at pH 8. Willstatter says " the only propertyof the enzymes which is independent of the purityis, as far as we -know, their qualitative specificity ;their adaptation to a definite set of reactions deter-mined by constitution and configuration." This iscertainly a hopeful circumstance. A substance whichunder all vicissitudes retains its most characteristicproperty will almost certainly be isolated. Thehistory of organic chemistry shows that this is onlya preliminary stage to ascertaining its constitutionand to its ultimate synthesis. Willstatter and hisschool may only succeed in adding to the equipment of investigators in this region, but it seems not ’,unlikely that the patience and brilliant insight whichmade green leaves and flowers reveal their secretswill penetrate some of the mysteries of the organised

’ ferments so closely associated with the life of man.

AURAL VERTIGO.

THE Bristol Medico-Chirurgical Journal ( 1927,xliv., 119) publishes an interesting little article byMr. E. Watson-Williams, in which he distinguishesthe classical, or rotatory, vertigo from the otherless well-marked forms, which vary from a vaguesense of impaired equilibrium to feelings that thepatient or his surroundings are moving up and down.In true rotatory vertigo the sensation is that thesufferer, or his surroundings, or both, are turninground and round ; the sensation of turning is conciseand definite, and even years after a slight attack thepatient’s description is clear and vivid. The apparent rotation is nearly always in the transverse plane-that is, in the plane of the base of the skull. Mr.Watson-Williams makes the point, which is not newbut is often overlooked, that vague feelings of vertigomay or may not be due to aural disease, whereasthis definite rotatory vertigo in the absence of cerebraltrouble is always due to it; the symptom may occurwithout tinnitus and even without deafness. Healso makes a more novel point, that the nausea ofvestibular origin is usually worse in the morning,and that patients suffering from it have thereforeno appetite for breakfast, though they may eat theirother meals heartily. Attacks of aural vertigo areso often ascribed by the patient to biliousness thatit is well worth while to insist, with Mr. Watson-Williams, that this definite rotatory vertigo is alwaysdue to disturbance of the mechanism of the labyrinth.

BIOCHEMISTRY AND MEDICINE.

A LARGE proportion of the funds available formedical research are nowadays allotted to laboratoryworkers whose investigations are apparently remotefrom the problems of the bedside and consulting-room.This policy is justified by the history of medicineand is only dangerous when allowed to bring clinicalwork into disrepute. If to-day the trend of ancillaryresearch is largely towards biochemistry that isbecause this science offers the largest uncultivatedareas to the pioneer. The horizons are illimitable andthe land is rich ; all that is necessary is its exploitation.For centuries there have been extending settlementsaround the coast from which the old world of medicinehas drawn new life, but until recently only a fewindividuals have devoted their lives to exploring thehinterland. Now at last these isolated journeys arebeing correlated and the country between them beginsto appear upon our maps. Fortunately, there aremore and more benefactors ready to finance the

survey and development of this new territory in theinterests of medicine, and an example of their wisdomis the Institute of Biochemistry opened on Wednesday

last at the Middlesex Hospital. This admirabledepartment will be directed by Prof. E. C. Dodds,who has himself brought back much that is valuablefrom his expeditions into unknown and difficultcountry. As he pointed out at the opening ceremonyat the Institute (reported on p. 195), it is apparentthat biochemistry " has already given us great andgenerally admitted benefits which are a tremendousencouragement to the pursuit of the study." Thevictories of the pioneers, he said, have already passedinto the routine of medical practice ; but while somuch remains unknown the investigators-howevermany-are still pioneers. The new Institute will bean admirable starting-point for fresh endeavour.

CHARLES CREIGHTON.

WE regret to announce the death of Dr. CharlesCreighton, the learned epidemiologist, which occurredon Sunday, July 17th, at Upper Boddington, wherehe had lived for some time in retirement. Hewas in his eightieth year, and will be but a

memory to most students of medical history, whilehis industry and erudition, which will be com-

mented upon in a future issue of THE LANCET,won for him no commensurate position in theworld.

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BASAL METABOLISM IN THYROID DISEASE.

Dr. Eggert Moller, of the University of Copenhagen,has recently published 1 investigations, by the Kroghmethod 2 into the basal metabolism in thyroid disease.His results are interesting, but serve rather to provethe usefulness of this particular method than tothrow any new light on the problems of basalmetabolism in thyroid disease. The Krogh closed-circuit apparatus seems to possess certain advantagesfor clinical work, the chief of which is its simplicity;several estimations can be made within an hour, anda graphic record provides an accurate control of thepatient’s respiration and enables the observer to readoff the oxygen consumption directly from the curve.The results have been found to agree satisfactorilywith those obtained by other methods. Opinion isalmost unanimous at the present time that this testis the best guide to the state of activity of the thyroidgland, and though, like all laboratory tests, it has itslimitations, it offers information which clinicalobservations by themselves could not supply. A largenumber of records of the basal metabolism in thyroiddisease have now been made, both in America andGermany and in this country. Dr. Moller’s findingsagree closely with them. He again raises the question,however, whether the metabolism is always abovenormal in Graves’s disease. A few years ago J. H.Means 3 called attention to a group of what he calledborderline cases, in which the clinical signs of thecondition were well marked though normal metabolicreadings were obtained. Dr. Moller has found thesame thing in his series of patients, and he too is ofthe opinion that a normal metabolism should notexclude a diagnosis of Graves’s disease. It must beremembered that there are certain conditions inwhich the basal metabolism will give a franklyincorrect impression in diagnosis, unless the previoushistory of the case is accurately known. For instance,patients with myxoedema who have been receivingthyroid extract, or those with Graves’s disease in aperiod of remission, may still retain many of thephenomena of the disease, and yet show a normalmetabolism. These considerations show that anyslavish adherence to the test as an index of diagnosisis inadvisable. The value of estfmating the basalmetabolism seems to lie especially in the differentialdiagnosis of doubtful cases and in following the effectsof different methods of treatment. There is no doubt

1 Acta Medica Scandinavica, 1927, Supplement xxi.2 Dansk Medicinsk. Sclskab’s Forhandl., 1921, p. 3.

3 Arch. Int. Med., 1919, xxiv., 645.