Looking at the Bradford map of 1750, I am wondering if the small circular features marked with arrows might be wells, and in particular, whether the green arrow might indicate the well mentioned near the school which gave rise to the name Well lane. These features seem to be particularly present around digbeth,, though do show up on other palces on the map. Unfortunately, this is the highest resolution copy I can find of the map. Presumably the original in the library would show things more clearly