Railway_electrification_system

Some street trams (streetcars) used conduit third-rail current collection. The third rail was below street level. The tram picked up the current through a plough (U.S. "plow") accessed through a narrow slot in the road. In the United States, much (though not all) of the former streetcar system in Washington, D.C. (discontinued in 1962) was operated in this manner to avoid the unsightly wires and poles associated with electric traction. The same was true with Manhattan's former streetcar system. The evidence of this mode of running can still be seen on the track down the slope on the northern access to the abandoned Kingsway Tramway Subway in central London, United Kingdom, where the slot between the running rails is clearly visible, and on P and Q Streets west of Wisconsin Avenue in the Georgetown neighborhood of Washington DC, where the abandoned tracks have not been paved over. The slot can easily be confused with the similar looking slot for cable trams/cars (in some cases, the conduit slot was originally a cable slot). The disadvantage of conduit collection included much higher initial installation costs, higher maintenance costs, and problems with leaves and snow getting in the slot. For this reason, in Washington, D.C. cars on some lines converted to overhead wire on leaving the city center, a worker in a "plough pit" disconnecting the plough while another raised the trolley pole (hitherto hooked down to the roof) to the overhead wire. In New York City for the same reasons of cost and operating efficiency outside of Manhattan overhead wire was used. A similar system of changeover from conduit to overhead wire was also used on the London tramways, notably on the southern side; a typical changeover point was at Norwood, where the conduit snaked sideways from between the running rails, to provide a park for detached shoes or ploughs.

Question: What was the area used for on the southern side of the London tramways where the conduit wove between the rails?
Answer: a park for detached shoes or ploughs

Question: The plow of a tram connects to what to power the tram?
Answer: third rail

Question: What system was more cost efficient, conduit third rail current collection or overhead wire?
Answer: overhead wire

Question: What is the main advantage of conduit third rail current collections as seen in Washington, D.C. and Manhattan?
Answer: to avoid the unsightly wires and poles

Question: A slot in the road that did carry a power cable was a slot used by what type of tram?
Answer: streetcar

Question: The overhead  wire method of powering streetcars was more unsightly than the conduit slot method, but it eventually overtook the slot method because it didn't have what downfalls?
Answer: higher initial installation costs, higher maintenance costs, and problems with leaves and snow getting in the slot

Question: Where did workers disengage the conduit third rail that was below street level so that they could switch it to overhead wire?
Answer: plough pit

Question: What type of streetcar system was used in Norwood?
Answer: system of changeover from conduit to overhead wire

Question: Originally in Washington, D.C. and Manhattan, what system of powering streetcars was more popular?
Answer: conduit third-rail

Question: Many large cities use conduit third-rail systems within the city, but what system outside the city?
Answer: overhead wire