shut out external noises and reduced those
within to a point where they no longer distract
the attention of clerks or customers
from the business of selling and buying. In
many, however, clerks are still forced to call
aloud for cash girls or department managers,
and the handling of customers at elevators is
attended by wholly unnecessary shouting and
clash of equipment.

Of all distractions, sound is certainly the
most common and the most insistent in its appeal.

The individual efforts towards reducing
it quoted above were stimulated by the hope

of immediate and tangible profit--sound-
proof offices commanding higher rents and
quiet stores attracting more customers. In
not a few cases, manufacturers have gone
deeper, however, recognizing that anything
which claims the attention of an employee
from his work reduces his efficiency and cuts
profits, even though he be a piece worker. In
part this explains the migration of many industries
to the smaller towns and the development
of a new type of city factory with sound-
proof walls and floors, windows sealed against
noise, and a system of mechanical ventilation.