This oddity is on the west side of North Magnolia Avenue between Vine and Fernwood. I can’t call it “undated” because I am assuming it originally did have a date, along with the rest of the Barnhart & Sons stamp.

I am supposing that this indicates the original sidewalk block was cut off, perhaps while the newer-looking walk north of it was laid. Why they would have done this, though, I have no good idea.