This was placed behind the engine and inconveniently in front of the pilot directly under the ammunition boxes. This lead to several cases of self-destruction in the hot summer of 18 as the phosphorus ammunition used as tracers/anti balloon ammunition self-ignited burning through the boxes and the tank with a subsequent unwelcome pyrotechnic display. Only when a German pilot managed to luckily avoid the full catastrophe counter measures were taken.
In the show and tell about the fuel gauge I have referred to a float mechanism which is also presented here. The gauge is an original Fokker DVII Maximall fuel gauge and you can clearly see the idea behind the mechanism in the picture. The float is set up in a tube and connected to the gauge indicator with a piece of string. Needless, to say inverted flying or actually anything but level flight might just give you a somewhat unreliable reading.