Precision tool making for the manufacture of telephone apparatus

There is probably no field of human endeavor in which hand labor has been more completely replaced by labor-saving devices than in the field of manufacturing. The design and employment of special tools together with semi- and full automatic machinery for operating them have reached a high stage of development and are probably more responsible than any other factors for the present age being generally referred to as the industrial age. The notable economies of present day manufacture result no more from the rapid production of parts thus made possible than from the interchangeability of these parts because of the accuracy with which they have been produced.