INDUSTRIAL ACTIVITY AND FATIGUE.

1292 is only a step from this to the theory of specificity Laboratory research often helps to disentangle the among the streptococci, and in rheumatism we are host of interfering factors which confuse the issue in familiar with the organisms of Beattie, Poynton and industrial practice. Evidence, at first inconclusive, Payne, and Birkhaug. All observers agree, however, has been reinforced from different sources-for that most cases of rheumatism do not yield organisms example, the increase in rate of output on short either from the blood or in local lesions, and none of shifts, the beneficial influence of short rest pauses, these has yet been recognised as the specific cause. the importance of high illumination in fine processes, The latest claimant is the " Streptococcus cardio- the deleterious effects of high temperatures on work arthritidis " of J. C. Small, which has lately attracted involving muscular effort, are among the conclusions some attention. Its claims, as now set out 32are which were tentatively made at first and as the result difficult to appraise. Only three of Small’s strains of many investigations, gradually came to be accepted. come from the blood ; most of them are from the The Board is steadily gathering and propagating throat, where streptococci abound ; and no evidence new knowledge, and even more important, is showing of any normal controls is given. Though the organism that improved conditions of work are beneficial alike is said to be non-haemolytic, to vary in its sugar to employers and workers. reactions, and to be specific in its agglutinations, no cultural characteristics are adduced which would STEEL DENTURES. make it possible to recognise the strains. Many of the references are " in the press," others are " personal DURING the late war the shortage of rubber and communications," and on the whole, technical details precious metals in Germany affected, among others, are inadequately presented. It may be noted that the dental profession, since the construction of tests of cutaneous sensitiveness are on the whole dentures involves either a vulcanised rubber or a negative, which is remarkable, since other workers gold base. As a substitute for these materials the have recently claimed specific results with their firm of Krupp began to experiment with stainless strains and, in fact, a surprisingly large number of steel as a denture base. The method soon passed rheumatic patients are Dick-positive. The author’s beyond the experimental stage, and before the end parsimony in bacteriological information, however, of the war dentures of stainless steel were being is balanced by his generosity in clinical detail. Patients made on a considerable scale. Even now that " are treated by vaccines, by soluble antigen," made both rubber and gold are freely procurable, steel by washing the streptococcus, and by antisera, and is still being used in Germany to some extent, especially by concentrated globulin precipitates. apparently with satisfactory results. In England Striking results are claimed ; very exact and ample experiments have been chiefly directed towards clinical details are quoted. Opsonic indices and finding a synthetic resin which could be coloured agglutination titres show a speedy upward change ; to resemble gum more closely than is possible with chorea disappears ; valvular lesions are ameliorated. vulcanite, and these attempts have been so far In considering these reports it should be remembered successful that it is hoped that vulcanite may soon that a relatively new claim to the identification of become obsolete. The German investigations have, the causal organism of rheumatic fever lends itself however, stimulated some preliminary trials of steel to criticism. Many independent investigators have in this country, and Mr. A. C. Hutchinson, in the incriminated the streptococcus, whereas few have British Dental Journal for May 15th, records some produced evidence to show that other organisms experiments carried out in the Manchester Dental might be to blame ; but even if its guilt be proved the Hospital with the cooperation of Messrs. Firth and question would remain, whether one strain of strepto- Sons, of Sheffield. It appears that Krupp’s use for dentures a rust-proof steel belonging to what is coccus is specific for the disease or whether a variety of strains may cause it. The trend of opinion all over termed the VA group, which has a high resistance to the world appears to favour a fresh trial of strepto- corrosion even when soft. It contains 20 per cent. coccal antisera for many diseases whose aetiology is of chromium and a medium content of nickel. A denture made of this material is only half the weight not as yet completely understood. of a gold plate of the same thickness, and in order to ensure equal strength the gold denture would have INDUSTRIAL ACTIVITY AND FATIGUE. to be twice as thick, and would weigh four times as THE history of human endeavour in the past, much. Mr. Hutchinson experimented with Firth’s whether in the construction of pyramids, cathedrals, Staybrite silver steel and found it possible to hammer industrial works, or engineering plants, has too often and swage the material into dental plates. Soldering, been a tale of effort directed by task- on the other hand, presented great difficulties and, masters with but little care for the well-being of the so far, the search for a suitable flux has not been labourer so long as the task progressed. Not until wholly successful ; but it was found possible to the beginning of this century did it begin to dawrl attach teeth to a steel plate by means of vulcanite, upon employers, as a class, that maximum production and the attachment appeared perfect. The work is is contingent on the fitness of the worker. In the still in the experimental stage in this country, and eighth annual report3 of the Industrial Fatigue the production of dentures which are satisfactory Board an account is given of the way in which the in the mouth is still some way off, though there seems work of the Board started and has since progressed, to be no reason why the German results should not We understand that in Germany and of the gradual expansion of its activities. The be repeated here. is complex, involving a technique not problems recently submitted to the Board for solution the process possible in a dental workshop, and that the actual cover a wide field and are of considerable importance. swaging of the steel is carried out by Krupp’s to They include hours of work in relation to the value models supplied by dentists. Nevertheless the method of rest pauses during long spells, and to the doubleshift system for women ; the physiology of ventilation has distinct possibilities and we hope that Mr. with special regard to heating by the panel system ; Hutchinson will continue so promising an experiment. vision and lighting ; accident causation ; vocational guidance, and other matters. Government departSPASM OF THE PYLORUS IN INFANTS. ments and industrial associations have sought information as to mining conditions, telegraphists’ ONE effect of the introduction of Rammstedt’s cramp, weight-carrying, and sickness in the cotton operation for hypertrophic stenosis of the pylorus in industry and printing trade. A further line of infants has been that a distinction is drawn between activity has been concerned with research into the ’, cases in which there is a palpable pyloric tumour and principles governing muscular activity, muscular ’ those in which there is not. With an experienced and noise and effects careful observer it is safe to say that if a tumour cannot be felt after several examinations, and visible 2 Amer. Jour. Med. Sci., 1928, clxxv,, 638. peristalsis is well marked, the case is probably 3 Eighth Animal Report of the Industrial Fatigue Research one of pyloric spasm, for which operation is contraBoard, to Dec. 31st, 1927. H.M.S.O., 1928.

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