A text-book on chemistry. For the use of schools and colleges (1866) (14776540605)

Identifier: textbookonchemi00drap (find matches)

Title: A text-book on chemistry. For the use of schools and colleges

Year: 1866 (1860s)

Authors: Draper, Henry, 1837-1882

Subjects: Chemistry Physics

Publisher: New York, Harper & brothers

Contributing Library: The Library of Congress

Digitizing Sponsor: The Library of Congress

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~w\ -wl_ poles^upward. The wires, W W, from the distant sta-tion induce magnetism in it, and draw down the softiron keeper, a. At the same time the clock-work, <?, isset going, and a strip of paper, p p, is drawn steadilyforward in the direction of the arrows. Whenever acurrent passes, and the keeper a is depressed, the point sis forced upward against the moving paper. If the cur- What is the construction of Morses telegraph ? 176 MAGNETIC AND DIAMAGNETIC BODIES. Fin. 149. e rent is but momentary, a clot only is made on the pa-per, but if it continue, a line is formed. Morses tele-graphic alphabet consists of a set of such dots and lines,which by varied grouping represent the various lettersand figures. Experienced operators do not, however,require the paper strip, but learn to distinguish, by the clicking sound of the keep-er falling on the magnet,what the transmitted mes-sage is. When different sub-stances are suspended be-tween the polar termina-tions of a horse-shoe elec-tro-ma

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1866

Library of Congress

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