Leavitt cancelling machine patent model
The Leavitt canceling machine was the first successful mail-processing mechanization. Its use reduced the manual labor required to postmark and cancel mail pieces. This is a working patent model for the improved 1879 device.
The Leavitt machine pioneered the basic characteristics shared by canceling machines. Feed rollers separated and introduced a piece of 'faced mail' into the machine, one at a time and spaced apart. The mail piece progressed to a rotating canceling die hub and ring die. After the postmark and cancellation impressions were made on the mail piece, it passed to a stacker. Mail pieces accumulated in the stacker until removed by the machine operator.
The Leavitt machine's chief limitation was that it could only be used with mail of very consistent size, shape, thickness, and stiffness. This amounted to postal cards, which in the late 1800s were growing in use as a direct-mail advertising medium.
Although of limited use, the Leavitt machine had a profound effect upon postal operations as well as the post office supply industry. It demonstrated feasibility of machine cancellation, spurring inventors and entrepreneurs to develop and introduce subsequent improvements. Likewise, it proved to Post Office Department management that the substitution of capital for labor to improve productivity was possible.