The consequences of this habitual attitude, for the technology of the machine era that presently follows, are worth noting. The mechanical inventions and expedients that lead over from the era of handicraft, through what has been called the industrial revolution, to the later system of large industry, bear the marks of their handicraft origin. The early devices of the machine industry are uniformly contrivances for performing by mechanical means the same motions which the craftsmen in the given industries performed by hand and by man power; in great part, indeed, they set out with being contrivances to enable the workmen to perform the same manual operation in duplicate or multiple--(as in the early spinning and weaving machinery) or to perform a given operation with larger effect than was possible to the unaided muscular work (as in the beginnings of steam power). In their beginnings the new mechanical appliances are conceived as improved tools, which extend the reach and power of the workman or which facilitate or lighten the manual operations in which he spends himself. They are, as they aim to be, labour saving devices, designed to further the workmanlike efficiency of the men in whose hands they are placed. The early history of steam power shows how closely this workmanlike conception limited the range of invention. It was first employed to pump water out of mines. In this use the pressure of the air on a piston, in a low-pressure cylinder, was brought to bear on a lever so suspended as to yield formally the same motion as a like lever previously moved by human muscle. After a long interval, sufficiently long to make the use of this intermittent pressure and the resulting reciprocating motion familiar and impersonal in men’s habitual apprehension, the reciprocating motion was turned to use to produce a rotary motion,--after the fashion suggested by the treadle of a lathe or spinning wheel, which was already familiar enough to have been divested of something of that fog of personality that had doubtless surrounded it at its first invention.[125] The next serious move in the development of the steam engine is the invention of the automatic valves, for admission and escape of steam from the cylinder. According to the ancient myth, a boy whose work it was to shift the valves by hand, contrived to connect them by cords with the moving parts of the machine in such a way as to lift them at the proper moment by the motion of the machine itself; so making the machine perform what had in the original concept of the valve mechanism been a manual operation. Later still, after the due interval for externalisation and assimilation of this mechanical valve movement as an impersonal fact of the machine process, further improvement and elaboration of the elements so gained has worked out in the highly finished mechanism familiar to later times.