Welcome to Oldgas. Your pump appears to be a Model 41 variation of the early Bowser pumps. These pumps were introduced around 1900 and were used in varying applications for many years right in to the 1950's. They were one of the first pumps to be used to fuel automobiles from remote tanks.They were equipped with a lot of different piping and valves for different applications. The one I have was actually labeled as a "Long Distance Gasolene Storage Outfit" and I have an old advertisement from 1911 showing it fueling a car from an underground tank.The number on your label is probably just a serial number and I couldn't find a reference to it in my books. The device atop the outlet spigot is probably a backflow preventer designed to keep fuel from draining back to the source when the pump stops operating.

Here is the one I restored. It had a large filter plus a gauge and gallon counter as accessories.

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