Modern Practice of the Electric Telegraph: A Handbook for Electricians and OperatorsD. Van Nostrand, 1872 - 160 páginas |
Términos y frases comunes
acid action adjusted annealed apparatus armature arranged attached binding screws button Callaud Carbon cells Chatterton's compound Cloth conducting conductor construction copper wire cuit Daniell Daniell cells dashes deflection diameter difference direction distance distant end dots earth effect Electric Telegraph electricity electro-magnet electro-motive force employed equal escape Fahr fault follows formula galvanometer gauge Grove battery gutta-percha Hypsometry inches increased instrument insulation J. B. Stearns joint resistance known resistance latter length lever lightning arrester line of tension line wire local battery loop main battery main circuit measure metallic method Morse needle number of convolutions ohms operator opposite ordinary placed plate platina porous cup portion position practice principle proportion pure copper relay magnet repeater represented resistance coils rheostat shown in fig signals solution sounder station statute mile sulphate switch tangent telegraph line terminal station tery testing tion total resistance type wheel versine zero zinc
Pasajes populares
Página 91 - The fundamental demands of health require the purification of a classroom by direct sunlight; but it is also necessary to introduce this all-important purifying agent in such a manner as to prevent as far as possible the direct rays of the sun from falling on the desks and books of the pupils while they are engaged in study. If the windows of a classroom are placed on the north side of a building located in any section of our country, very little direct sunshine will ever enter, and during the school...
Página 103 - To become an expert sending and receiving operator requires a vast amount of time and patience, and the most unwearied application. Remember that whatever is worth doing at all, is worth doing well.