A SELF-ACTING LOG.

Westport Times, Volume V, Issue 868, 30 September 1871, Page 3

A SELF-ACTING LOG.

A correspondent of the " Independance Beige" describes an invention by M. Ferdinand Esposito Faraone, of the Italian navy, called the Nausisrnograph. This is an automatic log-book which, with unerring accuracy, records the way made by the ship in her most unporceived deviations, the degree of her speed, and the amount of her rolling and pitching. The apparatus shows the position of the compass (and consequently the direction in which the ship sails) at every tenth turn of the screw or propelling wheel. According to the position of a line traced in pencil on a strip of paper the speed of a ship, her stoppages, and backward movements, may be exactly observed. The colour of the line changes automatically for the backward motion. On a third strip of paper the extent of the rolling and pitching is delineated by black and blue lines iu the form of a bow more or less bent, according to the state of the pea. The compass belonging to the apparatus is composed of a magnetised bar, which carries with it in its oscillations a small steel stem placed beneath it and magnetised in like manner. The combination of these two magnets forms an astatic system, but the preponderance of the magnetised bai* above makes it turn to the north. The steel stem below ends in a small pointed stvlus to penetrate the paper, and mark the position of the compass. To obtain this result the strip of paper travels under the two needles, and at every tenth revolution of the screw or of the paddle-wheels a small piece of mechanism lifts the strip, so that the paper itself comes to meet the puncture of the stylus and receive the impression of the index. The apparatus recording the speed of the vessel consists in a regulator, which rises or falls according to the rapidity of the rotation. The regulator is so managed that when the engine is working at high pressure, the pencil which follows the regulator maks its mark on a certain line of the paper ; for slackened speed the line marked will deviate according to the regulator, and change its position in accordance with the motion of the vessel during the time of the experiment. As to the pitching and rolling, they are automatically recorded by the play of counterpoises which oscillate round two axes, perpendicular the one to the other. One of these axes is parallel to the length of the ship, the counterpoise which oscillates round this axis measures the rolling, the other the pitching of the vessel. The nausismograph is, however, equally applicable to sailing vessels. The apparatus is the same in principal—the indications are given in the same manner. The motive power, which is, in one case, the engine of the ship itself, is in the other simple clock-work.— "Pall Mall Gazette.',