f a motor-driven cylinder having metallic pins placed
at intervals, and arranged spirally, around its periphery. These pins
correspond in number to the characters on the type-wheels. A keyboard
(not shown) is arranged above the cylinder, having keys lettered and
numbered corresponding to the letters and figures on the type-wheels.
Upon depressing any one of these keys the motion of the cylinder is
arrested when one of its pins is caught and held by the depressed key.
When the key is released the cylinder continues in motion. Hence, it is
evident that the revolution of the cylinder may be interrupted as often
as desired by manipulation of the various keys in transmitting the
letters and figures which are to be recorded by the printing instrument.
The method of transmission will presently appear.

In the sketch (Fig. 2) there will be seen, mounted upon the cylinder
shaft, two wheels made up of metallic segments insulated from each
other, and upon the hubs of these wheels are two brushes which connect
with the main battery. Resting upon the periphery of these two segmental
wheels there are two brushes to which are connected the wires which
carry the battery current to the type-magnet and press-magnet,
respectively, as the brushes make circuit by coming in contact with the
metallic segments. It will be remembered that upon the cylinder there
are as many pins as there are characters on the type-wheels of the
ticker, and one of the segmental wheels, W, has a like number of
metallic segments, while upon the other wheel, W', there are only
one-half that number. The wheel W controls the supply of current to
the press-magnet, and the wheel W' to the type-magnet. The type-magnet
advances the letter and figure wheels one step when the magnet is
energized, and a succeeding step when the circuit is broken. Hence, the
metallic contact surfaces on wheel W' are, as stated, only half as many
as on the wheel W, which controls the press-magnet.

It should be borne in mind, however, that the contact surfaces and
insulated surfaces on wheel W' are together equal in number to the
characters on the type-wheels, but the retractile spring of TM does half
the work of operating the escapement. On the other hand, the wheel W
has the full number of contact surfaces, because it must provide for the
operative closure of the press-magnet circuit whether the brush B' is in
engagement with a metallic segment or an insulated segment of the wheel
W'. As t