Connecticut Route 23

[kurumi]

In correspondence with AASHO advocating the designation of US 1N, 5W, 5E, 6N and 6S for its alternate US routes, Connecticut included a copy of its November 1931 blueprint map for proposed numbering in 1932. With a closer look, I noticed some erased numbers pointing to some earlier numbering proposals:



So CT 104 (now CT 137) was clearly going to be CT 27. There are erasures for nearby routes that are not legible, but I have an idea of what they might be. I think the geographical numbering system in 1932 was originally to start not with 29, but with 23 ... and possibly CT 21.

Yeah, I know, it sounds like this:


But there's some sense to it.
If CT 104(137) was 27, and CT 25 already was planned for the Bridgeport to Torrington route via New Milford, then 23 would be the next lower number available. And 21 might have been left for a Greenwich route to be determined later. Greenwich doesn't have such a route now, but did have a State Highway 358 before the 1932 renumbering, and the 1961 reclassification recommendations included two north-south routes for Greenwich:


So what does that leave for CT 123 (now 124) and 29 (they cross in the blue map, but 123 and 124 do not cross today)? CT 31 makes sense: at the state line, right between CT 29 and CT 33.

So 27 is certain; 23 and 31 are possibly; and 21 is less likely. Arguments in favor:
* they do form an orderly progression starting in the 20s
* 21, 23, 27, and 31 did not exist anywhere else in CT in 1932

Why did the low 20s get abandoned? Probably for number continuity across the state line. New York had recently numbered their routes (1930). A little neighbor state wouldn't have much influence on changing those.

Well, what about 29 and 33, which did continue to the state line? I don't know. They were changed decades later.

Why was 25 out of place? Good question. Maybe some engineer's favorite number.

[Alps]

I'm inclined to agree with 23 for the left number - it's 2something. Nice find.