Reports of the Massachusetts commissioners to the exposition at Vienna, 1873With special reports prepared for the Commission . B. LINES. 447 into by another, has caused in Europe the very general intro-duction of electrical apparatus for its prevention. The system of Mayer & Wolff, telegraphic instrument-makers of Vienna, which has been adopted and is exhibitedby the Nordbahn Railway of Austria, is one of the simplest ofthis class, belonging to subdivision a. The semaphore is adisc of the ordinary class, which is turned from the station inthe usual manner by a crank and wire. Around the suppor
Reports of the Massachusetts commissioners to the exposition at Vienna, 1873With special reports prepared for the Commission . B. LINES. 447 into by another, has caused in Europe the very general intro-duction of electrical apparatus for its prevention. The system of Mayer & Wolff, telegraphic instrument-makers of Vienna, which has been adopted and is exhibitedby the Nordbahn Railway of Austria, is one of the simplest ofthis class, belonging to subdivision a. The semaphore is adisc of the ordinary class, which is turned from the station inthe usual manner by a crank and wire. Around the supportof the semaphore is a small circular box of metal, used toprotect the connecting points of an electric circuit from expos-ure to the weather. As the semaphore turns to the positionof arrest, a projection upon one side of the support toucheswithin the box a brass spring, which is insulated from thesemaphore and its metal support, and connected by a wire tothe battery at the station. The support itself is connectedwith the ground, and thus an electric circuit is lY. illustrates the arrangement. Plate In circuit at the station is a trembling-sounder, which ringsas long as the disc is in position of arrest and the projectionon its support touches the spring. One of the advantagesclaimed for this particular apparatus is, that the bell does notcommence to ring until the disc is very near the position ofarrest, thus rendering false or accidental signals improbable. Where the semaphore adopted is an arm instead of a disc,it is evident that by changing the position of the connectingpoints from the side of the support to the top near the fulcrumof the arm, the above system could be used equally well. In 448 EXPOSITION AT VIENNA. that case, however, inspection of the points, -which is neces-sary from time to time in order to keep the connections per-fect, would be more difficult. The use of the foregoing or similar apparatus is the causeof that constant ringing of bell-
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Keywords: ., bookcentury1800, bookdecade1870, bookpublisherbosto, bookyear1875
