446 



NATURE 



[February 7, igr 



his letter that whatever be his mastery of the prac- 

 tical aspect of the subject, he is not well informed 

 on the scientific aspect as set out in the report of 

 the Royal Society Food Committee. He is par- 

 ticularly scornful of the view that it is more 

 economical to feed cereals direct to human beings 

 than to use tliem first for the production of pork. 

 By a travesty of the facts as to the common prac- 

 tice of pig-feeding-, and an obvious inaccuracy in 

 the numerical example given, he has no difficulty 

 in evolving his reductio ad absurdum. The whole 

 matter would have been scarcely worthy of notice 

 but for the public attack upon the position of the 

 scientific investigator in relation to food problems, 

 and a special meed of thanks is due to Prof. 

 Starling for the swiftness and effectiveness of his 

 defence. 



For the farmer the position is perfectly plain 

 and must be faced. The supply of feeding-stuffs 

 is very short, and live-stock of some kind must 

 be sacrificed. Above all, there must be no com- 

 petition between animals and human beings for 

 food which the latter can directly utilise. It is 

 under this latter head that the hand of restriction 

 falls most heavily on the pig. It is undeniable 

 that by pig-feeding much could be done to remove 

 the evil of the butter-queue ; but the bread-queue 

 would be infinitely more dangerous, and can only 

 be avoided by a rigid economy in the use of 

 cereals. 



THE INVESTIGATION OF INDUSTRIAL 

 FATIGUE. 



pROF. STANLEY KENT gives, in the papers 

 -■- mentioned below, 1 a general summary of the 

 results at which he has arrived in his studies of 

 the physiological signs of industrial fatigue and 

 some practical conclusions to be drawn from 

 them. It is pointed out that the state to be tested 

 is more complex than that of simple muscular 

 exhaustion, inasmuch as it is dependent on a 

 state of the nervous system, brought about, not 

 by muscular fatigue alone, but even more by ner- 

 vous fatigue, combined with worry, bad hygienic 

 conditions in the factory, ill-health, and insuffi- 

 cient food, as well as unsatisfactory home-life. 



The tests used were four in number — reaction 

 time, visual acuity, acuity of hearing, and height 

 of blood-pressure. They were selected as being 

 made quickly and easily, while being incapable of 

 control by the examinee. Curves constructed 

 from the results of these tests show a gradual 

 development of fatigue during the day, which re- 

 covers to some extent during the night, so that 

 there is a steady Increase through the week. The 

 increase due to overtime work is also indicated, 

 and the greater effect of a given amount of over- 

 time towards the end of the week comes out dis- 

 tinctly. Overtime work always causes a greater 



1 " Fatigue Induced by Labour." Bristol Medico-Chirurgical Journal, 

 July, 1917, vol. XXXV., No. 133. ' .— 



An Address on " Fatigue and Alcohol." Delivered before the Society for 

 the Study of Inebriety. Lancet, July 28, 1917. 



NO. 2519, VOL. 100] 



fatigue than the same amount of work at an early 

 part of the day. 



A factor which upsets the regular accumulation 

 of fatigue is that called by Prof. Kent the " Mon- 

 day effect." This is due to the lassitude and 

 disinclination to work present on Monday morn- 

 ing. The cause of this appears to be the partial 

 forgetting of skill during the period of rest, and 

 is the more obvious the greater the skill acquired. 

 The decrease of output on the Monday morning 

 is not, in fact, a case of fatigue, but of loss of 

 co-ordination. 



As a rule, the Sunday rest puts an end to the 

 accumulated fatigue of the week ; if not taken, 

 fatigue continues to increase until breakdown 

 occurs; unless, as usually happens, an automatic 

 slackening of work takes place, accompanied with 

 late arrival in the morning and so on. In any 

 case, there is loss of eflficiency. 



The measurement of fatigue by tests of the 

 kind described leads thus to the same conclusion 

 as that arrived at by Dr. Vernon from investiga- 

 tions of output, namely, that the maximum output 

 is to be obtained in most cases by reducing the 

 hours of labour. An equally important aspect of 

 the matter is that the worker is also given time 

 for culture and relaxation and for becoming a 

 "reasonable being instead of a mere machine." 



It will be seen that the fatigue investigated in 

 this research may be described as the feeling of 

 being tired, as distinguished from the exhaustion 

 of the muscles themselves. Now, it is just here 

 that the mischievous effect of alcohol shows itself 

 so clearly. Alcohol abolishes for a time the feel- 

 ing of fatigue, and thus enables the worker to go 

 on until the fatigue becomes worse than before. 

 He naturally takes more alcohol and so on. The 

 net result is no Increase of output — rather the re- 

 verse — while the state of the worker himself goes 

 from bad to worse. The effect of alcohol on mus- 

 cular work was strikingly shown In the march to 

 the relief of Ladysmlth, where the "drinkers " fell 

 out as if labelled. Some interesting results with 

 the four tests mentioned are given on p. i6 of the 

 address on "Fatigue and Alcohol." The re- 

 action-time of abstainers was uniformly less than 

 that of those who took alcohol. Moreover, the 

 depressing effect of a day's work was five times 

 as great in the "alcoholics" as in the abstainers. 

 Similar results were obtained with the other 

 tests. 



The conclusion Is that the only effect to be put 

 to the credit of alcohol is a psychical one, and that 

 this is transitory, leading to repeated doses. The 

 worker knows by experience that the discomfort 

 called fatigue can be diminished by taking alcohol, 

 and he naturally turns to It. The remedy Is ob- 

 vious. The fatigue Is determined by the condi- 

 tions in which men work. Improve the conditions 

 and fatigue and drinking disappear. Let us, 

 therefore, do our best to provide "the elements 

 of a healthy, full, and interesting life in place of a 

 mere existence without interest, without pleasure^ 

 and without hope." W. M. Bayliss. 



