Car air compressor ID help needed

A friend of mine's father passed away and in the garage was this air compressor (I think). His father was into Studebaker's and Hudson's. The owner's son believes this air compressor bolts onto the engine but that's about all he know's. I was hoping someone on this board could help me ID this cool old part and tell me exactly what it was used for. Thank you.

 

Many expensive cars had those bolted to the block from the factory.

Tire flats were very common and most cars had tire tools and patches for tubes. The compressor was for fixing flats on the road.

 

Very cool, thanks for the info.