Whistle, Steam

This is a steam whistle pressure regulator. It is made of brass. It consists of a main shaft, a lower body with a threaded pipe coming out the bottom, and a handle on the side. The lower body has the words "PHILA. Lonergan PENNA" stamped into it. On the flat edge above the pipe threading it says "40 LBS." The handle is curved and has a hole in the end, presumably to tie a rope to. There are some holes on the top of the widest part of the main body.