14,016. Mack, W. Oct. 4. Mechanical t e l e - graphs.-In signalling- apparatus for mines &c., two independentlyoperated pointers are provided, one remaining still when a predetermined signal has been given, and subsequent signal impulses being indicated by movement of the second pointer. Both pointers are returned to zero by cancelling-gear operated by the winding-drum when the signal is being complied with, or by the first impulse of a subsequent signal. A pointer l is secured to a shaft 2, which is also provided with a ratchet-wheel (not shown) co-operating with a detent 11. A second ratchet-wheel 4, loosely mounted on the shaft 2 and co-operating with a detent 10, carries a mutilated gearwheel 14 adapted to engage, when a predetermined number of signal impulses, for example three, have been given, with a gear-wheel 15 on a shaft 5 which carries the second pointer 6. A signalling-impulse given by a rope 9 raises a sliding bar 8, carrying a pawl 7 and secured by a chain 18 to a cylinder 19 working on a fixed piston 20. The cylinder 19, in its upward movement, operates a rocking lever 23, thus raising the detents 10, 11 and allowing the pointers to be returned to zero under the influence of weights 12, 13 or of suitable springs. On descent of the bar 8, the pawl 7 moves both ratchet-wheels and the pointer 1 one step. The descent of the cylinder 19 is adjustably retarded, so that subsequent signalling-impulses may be given without operating the rod 23. The ratchet-wheel operating the pointer 1 is mutilated so that, when three impulses have been given, subsequent impulses operate only the ratchert 4, and the gear 14, 15 rotates the pointer 6, the pointer 1 remaining at the cautionary signal. The pulley on which the weight 12 acts is loose on the shaft 2 and is connected to the ratchet 4 by a pin 16 passing through a slot 17 in the ratchet operating the pointer 1, this ratchet being returned to zero position by the pin 16 when the detents are disengaged. When the rope 9 is pulled to give a signal, a weighted sliding bar 32, Fig. 5, connected thereto is raised and held by a sliding catch 31 operated by a weighted lever 38. A pin 36 is thus held clear of one end of a lever 35, the other end of which carries a rubbertyred wheel 28, which is pressed against the winding-drum 27 by a spring 37. At the same time, a pin 42 passes above the end of a lever 41 connected to the detents 10, 11 through a chain 40, lever 39, and wire or like connexions (not shown). When the winding-engine is started, the drum 27 rotates the wheel 28, and an arm 30, carried by the wheel and connected bv a wire 29 to the lever 38, releases the catch 31. The bar 32 falls, the pin 36 engages the lever 35 and moves the wheel 28 away from the drum 27, and the pin 42 operates the lever 41 to raise the detents 10, 11 and cancel the signal.