A supplement to Ures Dictionary of Arts, Manufactures, and Mines, : containing a clear exposition of their principles and practice. . r key ; it can hence he made verydelicate, so as to act well by such currents as would not produce any motion in the instru-ment itself. The batteries which furnish the electricity lor doing the actual printing workin Morses telegraph, are in the same station with the instrument itself. The office of therelay is to receive the signals from afar, and to make the necessary connections with thelocal battery and instrument so as to print off the signals on the paper
A supplement to Ures Dictionary of Arts, Manufactures, and Mines, : containing a clear exposition of their principles and practice. . r key ; it can hence he made verydelicate, so as to act well by such currents as would not produce any motion in the instru-ment itself. The batteries which furnish the electricity lor doing the actual printing workin Morses telegraph, are in the same station with the instrument itself. The office of therelay is to receive the signals from afar, and to make the necessary connections with thelocal battery and instrument so as to print off the signals on the paper in the usual is obvious that the motions of the instrument and the relay are sympathetic, and thatwhat a trained eye can read off from the one, a trained ear can read off from the relays are constructed with much finer wire than is required for the instrument itself,so that the current circulating in them, although very low in force, is multiplied by a veryhigh number, and becomes equal to the delicate duty required of it. Fig. 273 is another illustration of the direct application of the electro-magnet without. adventitious aid. It represents a detent of McCallums Globotype for recording long tube contains small glass balls, which are retained therein by a detent attached tothe armature of an electro-magnet. Every time the armature is attracted, one ball is liber-ated and runs down into a grooved dial, where it remains for inspection. One or moretubes and detents are used, according to the nature of the signal required. As applied tothe signal-bell, {fg. 271,) three tubes are used—one charged with black balls, for indicatingthe number of bell strokes made; one with white balls, for indicating the bell-signals sent; one with spotted balls, for marking off the time in quar-- ^ ters of hours or intervals of less length. The balls, when liberated, all run into the same dial, and arrange them-selves seriatim. We may here refer to the case of another b
Size: 2594px × 964px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1860, bookpublishernewyo, bookyear1864
