ABOUT A YEAR AND A HALF AGO CHARLIE CHAPLIN EMERGED to film Modern Times, his animated critique of technological change. The hero of his piece, himself, a wrench in either hand, screwed nuts on bolts at a furious pace as they passed on an assembly line. At the time it seemed the ultimate in industrial mechanization, but already a portable electric nut-runner has been introduced on assembly lines. The device drives a nut tight in about three seconds, considerably bettering the time in which Charlie Chaplin or anyone else can do the job by hand and incidently changing some of the job's physical and psychological elements.

Siimilar technological changes are frequent in industry and their cumulative effects involve the whole question of the economic security of those who depend upon their work for a livelihood. Yet, despite widespread interest in the question surprisingly little information is available concerning the effects on workers of changes in industrial techniques.

Except in very rare cases, the effects of strictly technical changes on employment in a single industry or even in a single plant cannot be isolated or dissociated from other factors in industrial progress. Changes in industrial techniques are complicated and their effects on skills and jobs diverse. For instance, one highly important development of recent years is the adaptation of lifting and conveying devices to a wide variety of work. Here the effect is principally the displacement of unskilled men whose chief assets had been husky arms, backs and shoulders. Much less direct labor is now required for many of these operations, and the new skills are those of manipulating, oiling and maintaining the machinery.

The cigar-making industry on the other hand affords a contemporary example of the inroads of machines upon hand skills. The automatic long-filler cigar machine has affected chiefly men who after years of training, and aided only by a few tools, rolled out cigars by hand. Each machine installed has on the average displaced ten of these skilled individuals, chiefly men, and given four or five new jobs to unskilled women as machine tenders.

The coal loading machine represents another form of technological change. This machine, while it has not abolished any of the operations required in coal mining, has radically altered the organization of the work. Instead of highly skilled miners each working independently in his own "room" and performing during the day a wide variety of tasks, a gang of ten to twelve men "tend" a loading machine. Their work is coordinated by a foreman and each man is engaged in a single operation—timbering, drilling or tracklaying—like the subdivided, repetitive tasks in a factory. These loading crews produce more coal during the day than the same number of miners working by hand, and while the loader introduces some new machine tending skills the miner's old diversified skill isno longer needed. If he hopes to keep a job he must adapt himself to the "coal hog."

Many innovations, like the portable electric nut-runner, speed up work rather than change the skills required. Other electrical implements are being used for similar operations along the automobile assembly line—screw driving, drilling, tapping, grinding, sanding and polishing. No particular skill is needed to handle the tools; they may be turned over to the men who formerly clid the work with a hand wrench or screw driver. But these new devices, while they do not affect the skill with which the task is performed, do influence the total number of men who earn their living on the assembly line.

MACHINES OF OTHER TYPES CAUSE A DISPLACEMENT OF ONE group of skills but call into play different skills. With the advent of steel automobile bodies, skilled workers were replaced by skilled metal finishers, panelers, molders and hand welders. Again, unskilled or semi-skilled functions performed on single-purpose machines are often integrated by the introduction of multiple-purpose machines which require a trained operator. For example, a new automatic welding-machine performs six different operations in the manufacture of radiator tubes for transformers; it takes strip steel from a roll, presses six lengthwise grooves into the stock, folds it over, crimps the two edges, welds them together, and then cuts off the welded tubes into required lengths.

A still further technological development is illustrated by the substitution of remote control of automatic operations for direct control of machines supervised by operators. In some hydro-electric plants there is not a single worker. Operations and control are all carried on by electrical devices which automatically "report" by telephone to a central station. A man in the station transmits "orders" back to the plant, to be automatically obeyed.

In the total picture of technological change, the increase in the number of trained technicians, in engineering, chemistry, and other special fields, is an important factor.

The introduction of more efficient machines may result directly in the displacement of workers and create a demand for workers with another type of skill or ability. But there are also other, less obvious, ways in which technological change affects employment. For example, improved methods may enable one plant to lower its prices, and so divert business from competitors. Or, the result of a widespread technological change in an industry may be a lower price and a wider market which so stimulates employment in the same or other industries that the number of workers displaced is offset by the absorption of as many or even more workers, though not necessarily the same ones. Again, without reducing the total number of employes, technological improvements sometimes change occupational requirements, bringing about a labor turnover which results in at least temporary unemployment for those displaced.