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It showed that electric currents being conveyed by wires to a distance could be there caused to deflect magnetic needles and thereby to give signals. It was, in a word, a hint at the application of electricity to telegraphic purposes, but nothing more—for it provided no means of applying that power to practical uses. His apparatus consisted of two instruments for giving signals by a single needle, placed in different rooms, with a battery belonging to each; copper wires being extended between these two termini. The signals given were a cross and a straight line, marked on the opposite sides of a disc of card fixed on a straw, at the end of which a magnetic needle was suspended horizontally in galvanometer coils by a silk thread. The effect of this arrangement was, that if a current was transmitted from either battery, when the opposite ends of the wires were in connexion with the distant telegraphic apparatus, either the cross would be there exhibited by the motion of the needle one way, or the line by its motion the other way, according to the direction of the current. The apparatus was worked by moving the ends of the wires backwards and forwards between the battery and the coils.”
Dr. Hamel’s third point is, that Muncke’s copy of Schilling’s telegraph was imported by Cooke into England, and there adopted. This seems to be the Doctor’s chief error. For as regards the form and arrangement of the instrument as described by himself, or others, no one
