. The street railway review . ng the pipe system at equalpotential throughout, and for insulating sections or insulating joints, some of which have been patented. The idea of these sections or joints, asadvanced by their advocates, is to break up the metallic continuity of thepipe line and reduce its conductivity, and thus prevent its serving as a pathwhich the return current would naturally choose. The effect of thus divid-ing a pipe system into a small number of sections would hardly be worthconsidering, as the ground itself is a good conductor, and the current wouldleave one section only to
. The street railway review . ng the pipe system at equalpotential throughout, and for insulating sections or insulating joints, some of which have been patented. The idea of these sections or joints, asadvanced by their advocates, is to break up the metallic continuity of thepipe line and reduce its conductivity, and thus prevent its serving as a pathwhich the return current would naturally choose. The effect of thus divid-ing a pipe system into a small number of sections would hardly be worthconsidering, as the ground itself is a good conductor, and the current wouldleave one section only to go to another, passing through the earth around theinsulating joint just as it does around the lead joint in a cast-iron main. Toentirely destroy the conductivity of the pipe line, it would be practicallynecessary to make it up entirely of insulating sections, which, as non-metallic substances are not generally recognized as good material for under-ground water pipes, and for other f(;ually obviovis reasons, would be FIG. *>. The conductivity of the tracks may be, of course, increased by the use ofheavier rails, heavier bond wires and improved methods of bonding, or bythe introduction of welded joints, or by making practically continuous rails;but the continuous rail itself is at best but a palliative of the electrolyticinjury. The rails are not insulated from the ground, and the pipes would stillcarry, and be affected by a large portion of the current, as is clearly shown bynumerous electrical surveys and reports of serious damage in cities wherethe best tracks known to modern science are in use. In conclusion, the author recommends the double trolley system, overhead,as at Cincinnati, or conduit, as in \\*ashington and New York, as the onlyperfect method of keeping currents out of the ground and preventing elec-trolysis. NEW YORK FRANCHISE TAX CASE. The New York Supreme Court has granted a writ of certiorari,returnable in October, directing the Municipal Board of
Size: 1411px × 1770px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., book, bookcentury1800, bookdecade1890, booksubjectstreetrailroads
