Inasmuch as no regular apprenticeship period is served for machine operating, a special effort was made to secure data relating to the time usually required for the worker to learn the operation of each tool well enough to earn average wages.  In this matter the individual opinions of foremen and superintendents differed widely, but when the reports from all the establishments visited were compared, a sufficient degree of uniformity was found to serve as a basis for estimating the amount of experience workers of average intelligence would need, under normal shop conditions, in order to become fairly proficient.

There was practical unanimity in fixing the period at four years for tool makers and three to four years for machinists.  Higher estimates were received from the superintendents of plants doing a jobbing business or manufacturing high grade machine tools than from the specialized shops making a single product.  The superintendents of automobile manufacturing plants, where the standard of quality in production is necessarily high, gave the lowest estimates of all.  Table 20 shows the estimated time required to learn the various types of machine work.

TABLE 20.—­ESTIMATED TIME REQUIRED TO LEARN MACHINE TOOL WORK

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Workers                     | Time required        |
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Grinding machine operators          | 12 to 15 months      |
Lathe hands                         |  6 to 9 months       |
Planer hands                        |  6 months            |
Gear cutter operators               |  6 months            |
Turret lathe operators              |  4 to 6 months       |
Screw machine operators             |  3 to 6 months       |
Bench hands                         |  3 to 6 months       |
Milling machine operators           |  2 to 4 months       |
Drilling machine operators          |  2 weeks to 4 months |
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The weakness of specialization, with its constant tendency towards the substitution of semi-skilled operatives for trained workmen, lies in its failure to provide a body of workers from whom to recruit the large directive force needed in any scheme of production based on semi-skilled labor.  This condition is regarded by many employers with grave concern, and in a few plants apprentice schools designed primarily to train future foremen have been established.

Practically all the foremen in the shops visited had received an all-round training as machinists, and there are few opportunities for promotion open to men who have not a general knowledge of the trade.  On the other hand, such general knowledge is only one of the requisites for advancement.  Others are initiative, resourcefulness, tact, self-control, ability to get along with men, and a disposition to subordinate