A DIFFERENTIAL COUNTER FOR STEAMSHIPS.

Kumara Times, Issue 858, 1 July 1879, Page 4

A DIFFERENTIAL COUNTER FOR STEAMSHIPS.

[PKOM THE TIMES.] There has recently been introduced on board tnevessels of tne French naval Equadron in the Mediterranean a differential counter, designed by Cavtain Valessie, to regulate the rate of speed of steamships. It has been highly appreciated by the commanders. 8y means of it the ship can he. kept, much better than previously, at thV cpeed assigned to it among the other ships of the squadron and, by simple observation, of the instrument, an indication is had of the ■ means of regaining the proper post, by advanclcg or falling back, when the vessel may have lost that poßt through momentary deficit or excess in the engine's velocity. Tbe apparatus consists, firstly, of a watch or timekeeper, the hand of which, beating seconds, makes the circuit of the face in .one minute. This watch is fixed on a rotating-boss, which, is centred- with the same axis as the hand, and to which the engine of_ the Bhip imparts a movement of Rotation in an opposite direction to that of the hand. By means of gearing for variable multiplication of the speed, the engineer establishes for each rate of going of th» engine such a relation between the numb** •of turno of this engine and that of the basa which carries the watch, that this latter makes precisely one turn per miauta. for the desired speed-rate of the engine. The hand of then remains motionless opposite a fixed mark on the case of the instrument so long as the engine is kept at the speed, commanded. If the speed gets quicker, the hand goes back from the fixed ■S^Ju lf ? lower - forward. The arrangeSr L glVeS ? Yer y seE sitive indication, enablmg the engineer, to keep the engine at the rate commanded. Further, if the hand be a few seconds behind or before, it indicates the number of turns made in excess or deficit, Mid the attendant has merely to accelerate orretard the pace till the hand comes op po Bite its mark, m order to bring the shm to its proper post again. This invention has re SuS,"