But the bow for overhead wire is clearly seen on the roof. http://transphoto.ru/photo/646649/ - the same for this photo. Still unclear how these cars are powered here.
> Other European hybrid tramway networks included Paris, Nice, Lyon, Lille and Bordeaux in France; Berlin, Vienna and Budapest. In Paris, the conduit sections were frequently very short, requiring cars to change from overhead to conduit and back several times in one journey. The last conduit line in Paris closed in 1936, while the last Bordeaux conduit car ran in 1953. The conduit systems in Berlin, Vienna and Budapest were very short-lived. All three were replaced by overhead working before World War I.
> The small exhibits are also very interesting. To the left we see a cutaway of the Budapest electric tram conduit system designed by Siemens&Halske in the late 1880s. In contrast to other conduit systems, IT WAS LOCATED UNDERNEATH ONE OF THE RUNNING RAILS, and not between the two rails of the track. Also, unlike in Vienna, where they used an improved version of the Budapest conduit with the running rails used for current return, both positive and negative electric poles were located in the shaft, by using two angle-irons, one for each pole. To the right we see different current collectors for this system, which proved to be problematic at the start, as the current collector could only be raised (removed) at designated places. Later they introduced more flexible current collecting "ships", which could be raised anytime, anywhere.
You can see conduit photos from museum by last link. And I was right about gutter for conduit :)
So I guess the explanation given by Aviateur is right. My first thought was about retouch, too, but there are even no proper poles for overhead wire here. Thanks everyone.
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