I have this nh that I want to rebuild its.hard to say if it's
Early or late it has a brass throttle arm and a steel choke arm
I think it's a center drain but I don't know for sure the bowl Assy. Was missing when I found it in the bottom of a pail
Of rusty parts. Tag says. Patented 9-5-1911
Looks like a "Straight thru" to me. Highly sought after by some T guy's.
It does not have a notch in the bottom of the main body so it had a side drain originally. The bowl in your photos looks like one for a Kingston L4.
I agree with Royce. Looks like a plug is missing in one of the passageways. You had better clean it out, and re-plug it. NH bowls are pretty easy to find.