hold the material firmly in exactly the position in which the machine-
tool can be brought to bear on it in the right way, and without wasting
meanwhile too much time in taking grip of it. But this can generally be
contrived when it is worth while to spend some labour and expense on it;
and then the whole operations can often be controlled by a worker, who,
sitting before the machine, takes with the left hand a piece of wood or
metal from a heap, and puts it in a socket, while with the right he
draws down a lever, or in some other way sets the machine-tool at work,
and finally with his left hand throws on to another heap the material
which has been cut, or punched, or drilled, or planed exactly after a
given pattern."

Professor Marshall summarizes the tendency in the following words--"We
are thus led to a general rule, the action of which is more prominent in
some branches of manufacture than others, but which applies to all. It
is, that any manufacturing operation that can be reduced to uniformity,
so that the same thing has to be done over and over again in the same
way, is sure to be taken over sooner or later by machinery. There may be
delays and difficulties; but if the work to be done by it is on a
sufficient scale, money and inventive power will be spent without stint
on the task till it is achieved. There still remains the responsibility
for seeing that the machinery is in good order and working smoothly; but
even this task is often made light of by the introduction of an
automatic movement which brings the machine to a stop the instant
anything goes wrong."[16]

Since the economy of production constantly induces machinery to take
over all work capable of being reduced to routine, it would seem to
follow by a logical necessity that the work left for the human worker
was that which was less capable of being subjected to close uniformity;