875

Indians. From the dietary of seal and fish consumedby Eskimos a century ago he calculated the aliments andnutrients obtained. It seems that they fared very wellprovided they could catch the seals, and there was

certainly no deficiency of vitamins. Although the dietwas very rich in protein, rich in fat, and poor in carbo-hydrate, there was no reason why it should give rise toketosis, but it was perhaps surprising that arterio-sclerosis was so rare. Indeed, the other diseases ofcivilisation (such as diabetes mellitus, tuberculosis,appendicitis, cancer, and dental caries) were extremelyrate among the Eskimos, and still are in those few placeswhere they have not been contaminated by white men.Importation of the white man’s diet brings with ithis diseases. This has been particularly obvious inthe ease of the Indians : the Crees visited by Dr. Sinclairin 1943 used to be hunters subsisting on an excellentcarnivorous diet ; but now their dietary is mainlybannock, white flour, lard, and sodium bicarbonate,mixed together in haphazard proportions. This fatehas also overtaken the Australian aborigines, whosefood was discussed by Mr. G. H. Bourne, D.sc. Nowthey consume white flour and sugar, whereas previouslythey subsisted on various animals ranging from marsupialsand buffalo to moths and caterpillars. In the last paper,Dr. B. M. Nicol discussed the protein in the diet ofthe Isoko tribe of the Niger Delta. Here again was atribe largely carnivorous in habits who consumed fish,snails, snakes, and lizards ; but to these they addedyams, cassava, palm oil, and palm wine.

It is perhaps unfortunate that there was not enoughtime to correlate the dietaries of these different peopleswith the incidence of diseases among them : this is a

subject of great interest to which far too little attentionhas been paid. Sometimes dietary and culinary habitsare dictated by expediency : the Eskimos obtain largeamounts of vitamin C from the skin and stomach contentsof the animals they eat, and most of their food is eatenraw. These habits arise, not from a knowledge of

dietetics, but from the necessity of eating as much aspossible of the slender food-supply and from the diffi-culties of cooking in an igloo. Physiologists might wellstudy the Eskimo further, particularly when such interestis being taken in survival under Arctic conditions. Andsome of the problems appear to concern physicists ;for Dr. Sinclair mentioned that the Yakuti are allegedto be able to eat 36 lb. of beef and 18 lb. of butter (about120,000 calories) in under three hours. Throughout thisinteresting discussion it appeared that there were serious-gaps in our knowledge, severe limitations in our choiceand enjoyment of food, and a surprising difficulty indescribing tastes. It is doubtful if we have advancedmuch beyond the problem of cooking a snark.

1. Westall, R. G. Nature, Lond. 1952, 170, 614.

PORPHOBILINOGEN

PORPHOBILINOGEN, the Ehrlich-reacting material whichappears in the urine of acute porphyria, has long beenone of the veiled figures which haunt the course inclinical pathology. It has some diagnostic and prognosticinterest to the clinician, but its main importance is itsassociation with the whole subject of porphyrin chem-istry. In this connection the biochemist has had it onthe list of " wanted " substances for some time, and nowa particularly elegant piece of research by Westall hasculminated in its crystallisation. This is a considerablefeat, since the insolubility of porphobilinogen in mostnon-aqueous solvents and its instability make it very’unmanageable. Its isolation has been made possibleby the development of ion-exchange resins as chromato-graphy media, and by the observation that porpho-bilinogen can be precipitated from urine by mercuricacetate.

Porphobilinogen has usually been thought to give rise,under certain circumstances, to uroporphyrin.. This

view, recently contested by Hawkinson and Watson 2has now been proved correct. The change takes placeon boiling at any pH between 1 and 8, the largest yieldbeing obtained in 0-SjV HCI. On standing at room-temperature, porphobilinogen is slowly converted to thereddish non-porphyrin pigment, porphobilin.The importance of any substance which can give rise

to porphyrin lies in the possibility that it may be anatural intermediate in porphyrin synthesis. Thenumber*of these known or suspected precursors isgrowing-recent work by Weathera]l at the LondonHospital, for instance, strongly suggests that in the lead-poisoned rabbit all the urinary porphyrin is present asprecursor at the moment of excretion. The nature of

porphobilinogen has been the subject of several guesses.The most popular has been that it is a monopyrrole ormore probably a dipyrrole-possibly a dipyrrylmethaneof the type postulated theoretically as an intermediaryin porphyrin synthesis. This guess can now be tested.Whether porphobilinogen in the urine is an overflow ofa normal metabolite which is produced in excess, or

whether it is in itself an abnormal material, cannot yetbe settled. But some interesting light on porphyrinsynthesis and on congenital errors of metabolism is

likely to come from further work on porphobilinogenwhich is now in progress.

2. Hawkinson, V. H., Watson, C. J. Science, 1952, 115, 496.3. Weatherall, M. Biochem. J. (in the press).

FIFTY YEARS OF MIDWIFERY

IN 1900, out of every 300 London mothers giving birth,one died ; ’in 1950 one died out of every 1880. The firstMidwives Act, which set in train the events which led tothis extraordinary change, was passed in 1902 ; and onOct. 28 the Royal College of Midwives entertained theMinister of Health at their celebration of the goldenjubilee of this momentous piece of legislation. Before itwas passed, as the Tanchester Guardian (Oct. 27) recalls,women who could not afford to pay a doctor to attendthem in confinement relied on the Gamp, who wassometimes kindly and experienced, but all too often cutto the pattern of the immortal Sarah. It is true that in1872 the Obstetrical Society of London, after failing topersuade the Government to take action, started theirown examination for midwives, though they could notcompel women practising midwifery to take it ; andwhen the Midwives’ Institute, now the Royal College ofMidwives, was founded in 1881 it immediately undertookthe further training of women who held the ObstetricalSociety’s certificate. It took eleven years, and all themoney the institute, could raise, before the Act makingit an offence for an uncertificated woman to attend a

delivery (unless she was working under a doctor) reachedthe statute-book. The official qualification became thecertificate of the Central Midwives Board; and after 1910the board recognised the institute as a lecture centre forpupil and postgraduate midwives. The increasing workof the institute in the interests of maternity and childwelfare led to its change of status, in 1941, to the Collegeof Midwives, and in 1947 to the royal recognition.’

Today the mother has many services at her command.The midwife, however, remains a key figure in the team,and may fairly take much credit for the fall in thematernal mortality-rate. Nor has her part been small inthe saving of infant lives : since 1902 the infant-deathrate -has fallen from 133 per 1000 live births to 23 per1000 in the third quarter of this year—-the lowest figureon record.

THE ASSISTANT EDITOR OF THE LANCET

WITH great regret we announce that Dr. EdwardClayton-Jones, because of continuing ill health, hasresigned. The Proprietors have, appointed Dr. Ian

Douglas-Wilson to succeed him as assistant editorfrom Nov. 1.