Ternant, A. L. (Alcide Ludovic), 1832-1884 · London ; New York : G. Routledge and Sons · leaf 36
THE TELEGRAPH. i8 the normal to the mirror passes through the meridian then occupied by the sun, the reflected beam will be projected towards the pole. A second mirror, the centre of which is on the prolongation … Fig. 5. of the arbor of the first, and so inclined that the rays it receives from the first are reflected to the distant station, completes the apparatus. This second mirror, of course, remains in one fixed position.
Telegraph
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