Even where the man's dexterity or skill is no greater than that of the woman's his wages still tend to be greater. Usually if an employer can get both men and women workers he is prepared to pay somewhat more to a man even though the man's output per hour is no greater than that of a woman. Put bluntly, a male worker is less bother than is a female worker. A female staff is always to some extent an anxiety and a source of trouble to an employer in a way that a male staff is not, and to many employers it has the great defect of being less able to cope with sudden rushes of work. Men are, after all, made of harder stuff than women, and only in the grossest cases do we ever give a thought to men being overworked. With women, however, not only the Factory Act, but also decent feeling requires an employer to be vigilant to see that undue strain is not placed on them. The greater remuneration of men in those occupations where both men and women are employed on the same processes is then due to the fact that the men are preferred to women, and employers are accordingly willing to pay more to get them. Such occupations, however, probably form the exception rather than the rule, and we have to consider the cases where there is apparently no sex competition whatever. The nursery-maid wheels the baby's perambulator on the pavement; the mechanic drives his motor van in the road. They do not compete for employment in any sense. Generally, indeed, custom has indicated with a fair degree of preciseness what are men's occupations and what are women's. Why, then, in distinctively women's occupations should the wages paid be lower than men's? The answer is not easy, but the key to the problem is to be found in the broad statement that the field of employment of women is much more restricted than that of men. Hence the competition of women for employment reduces their general wage level to a lower point than that of men, or, as an economist would put it, the marginal uses of female labour are inferior to those of male labour.