Would there be gallon markers on the side of the cylinder on this pump, or would there be inside gallon markers? Have a pump that seems to have the inside Wayne gallon markers in it, but they seem to be just hanging there. Anybody ?? 12 x 27 cylinder.

My understanding is that they had etched cylinders. I found an Ottawa last year that was laying on the ground for more than 50 years, the cylinder had broken there where it laid. I dug up the area and did not find any markers I also couldn't find any glass with etching on it either.

Here is a picture of the base or whole unit.

Here is a pic from Jacks' book. Looks like it's missing the lighting conduit and the skins are not correct. Also from what I can make out the cylinder had etched gallon indicators. Hope this helps.

The one that I have has an etched cylinder.

There are no skins, just a 8" cast iron column with the two doors for it. You are probably right about the cylinder etching, or there is the inside markers that look like that. I would think the etch would be the correct one though.
Thanks

Ottawa pumps only used etched cylinder. Also came in a 15 gallon model.

Every Ottawa visible I have ever seen has had an etched cylinder! No gallon markers.