This photo is of the old Dome gas service station in Takoma (or possibly Takoma Park). The caption says Takoma Park, but according to this page, the location was at Cedar and Blair, just inside the District line. This would also make sense because the railroad tracks in the background are still there today.
Source: Shorpy
That appears to be the station behind the fuel dealer, with a siding coming off on an angle. Since the siding is on a trestle it can be assumed this fuel dealer started as a coal distributor, then expanded into petroleum. Interesting to see the tank car of fuel being unloaded on the coal trestle.