We find, therefore, a marked similarity in the curves relating accidents to hours of labour, accidents increasing progressively up to the end of the morning's work, and again in the late afternoon as the day's work draws to its close.Recent German statistics show that the highest rate of accidents is during the fourth and fifth hours of morning work.
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That over-fatigue connected with industry is responsible for large numbers of nervous disorders is, of course, generally admitted.The growing prevalence of cardiac neurosis and of neurasthenia in general among working-people is attested by many medical authorities, especially in occupations where long strains of attention are involved.But the general enfeeblement and loss of resistance power to disease germs of all kinds are even more injurious consequences of over-exertion.Many experiments attest the fact that fatigue reduces the power of the blood to resist bacteria and their toxic products.
§5.So far I have dwelt exclusively upon the physiological nature and effects of fatigue as costs of labour.But due account must also be taken of the psychical or conscious costs.Much work in its initial stage contains elements of pleasurable exercise of some human organ or faculty, and even when this pleasure has worn off a considerable period of indifference may ensue.Though boredom may set in before any strain of fatigue, the earlier period of ennui may not entail a heavy cost.But, when fatigue advances, the irksomeness brings a growing feeling of painful effort, and a long bout of fatigue produces as its concomitant a period of grave conscious irritation of nerves with a subsequent period of painful collapse.Where the conditions of work are such as to involve a daily repetition of this pain, its accumulative effect constitutes one of the heaviest of human costs, a lowering of mentality and of moral resistance closely corresponding to the decline of physical resistance.Drink and other sensational excesses are the normal reactions of this lowered morale.Thus fatigue ranks as a main determinant of the 'character' of the working-classes and has a social significance in its bearing upon order and progress not less important than its influence upon the individual organism.
§6.I have dwelt in some detail upon these phenomena of fatigue, because they exhibit most clearly the defects of the working life which carry heaviest human costs.These defects are excessive duration of labour, excessive specialisation, excessive repetition, excessive strain and excessive speed.Though separate for purposes of analysis, these factors closely interact.Mere duration of labour does not necessarily involve fatigue, provided it carries the elements of interest, variety, and achievement.
The degree of specialisation or subdivision of labour counts on the whole more heavily.But even a high degree of specialisation is alleviated, where it contains many little changes of action or position, and affords scope for the satisfaction attending expert skill.It is the constant repetition of an identical action at a prescribed pace that brings the heaviest burden of monotony.
