substantially constant speed, the switch and the driver being coupled in such a manner that the pull of the magnet will be effective to release the switch instantly from the 510driver when the magnet is energized, and the rotary driver being so combined with the switch as to begin to operate the latter immedately on the deënergization of the magnet. This will be better understood by 515referring to Figs. 1 and 9, in which 21 represents the armature of the relay magnet 19, which magnet, as before stated, governs the operation of the first translating mechanism. This armature is secured in this case to one 520arm of an angle-lever 22 pivoted about the axis 23 of a rotary driver 24, which in this case is a worm-gear forming the terminal member of a train of worm gearing driven from a common driver 25, which will be 525rotated in one direction of a substantially constant speed by any suitable means, this driver being preferably the armature-shaft of a small electric motor 26, the direction of rotation of such armature shaft being 530indicated in {{spl2|1|Fig. 1|#S1} by an arrow. The initial member of the train of worm gearing operated by this main driver 25 is a worm 27 and the intermediate elements are a worm gear 28 in mesh with the worm 27, and the 535worm 29 in mesh with the worm gear 24. The object of this gearing is to reduce the speed of the main driver 25 to a very slow rotary movement of the worm gear 24 with which the angle-lever 22 directly coacts. 540The angle-arm or lever 22 constitutes one element of a switch the main member of which is a spring-arm 30, preferably insulated from the lever 22 and coacting with a contact 31 constituting a terminal of a circuit 545controlled by switch-arm 30. In this case the switch is adapted to he coupled to the worm-gear 24 by a frictional connection. Between this arm 22 and the worm gear 24 a frictional connection (not shown in 550detail) may be interposed for the purpose of coupling these parts together, or any other suitable means may be employed for effecting this result. The parts shown are the same as those illustrated in my 555prior application hereinbefore mentioned. This frictional connection should always be so adjusted as to permit the arm 22 to slip when the armature 21 is attracted by the relay magnet 19 and also when the long arm of the 560angle-lever 22 comes in contact with the stop 32. The worm great 24 travels slowly in the direction indicated by the arrow in Fig. 17 and hence begins to return the armature 21, the lever 22 and the switch-arm 30 565to their normal positions show in said view as soon as the relay magnet 19 is deëergized. This slow and regular return movement of these parts will be variable in extent, and the length of the movement will 570depend upon the length of the time-constant of the interruption of the signals received. If the break in the circuit is the vibratory interruption which separates successive electrical vibrations the parts 21, 22°and 30 will have only a partial stroke, and the switch-arm575 30 will remain in engagement with the contact 31. If, however, the interruption is of longer duration, as for example, the interruption following a dot or a dash of the Morse or other telegraphic code, the parts580 21, 22 and 30 will move a greater distance corresponding to the greater length of the time-constant of such break as compared with the time-constant of the vibratory interruption. Usually on the reception of a585 break following a dot or a dash the worm gear 24 will carry the parts 21, 22 and 30 with it until the long arm of lever 22 is in contact with the stop 32, by which time the contact-arm 30 will have moved away590 from the contact 31 and will have broken the local circuit.
