Bought a Colchester Dominion 15 lathe last year. I looked at it in its dark, gloomy and cluttered basement and there was all sorts of "stuff " underneath the lathe including an air compressor cylinder. The wiring was weird, a micro switch under the forward/reverse lever in the neutral position, a water pump pressure switch, an old fuse panel running from an equally old breaker panel. We fiddled around with it for quite a while and got it to spin but didn't know how we did it so we couldn't repeat the process. After buying it I had to get it out of there so I started clearing all the stuff from under and around the lathe. The compressor cylinder wouldn't budge, got some bigger lights and found it was bolted to a scabby angle iron frame that the lathe was sitting upon. So the previous owner had the brilliant idea to rig the lathe to make compressed air when running in neutral, hence the weird wiring. Good idea except the reciprocating load from the compressor caused the gears on the input shaft to chatter themselves into oblivion.