Out of order Chairman.

       Unfortunately I didn't take a notebook onto the Canal; well, more accurately I did, but no Pen - SO - I'm having to rely on the EXIF for what day it was.
       This was the first of two "oddities" seen.  I know that because I'm backblipping the entire week.
       As you can probably guess/imagine with the Canals being built thus:-
"There were two concentrated periods of canal building, from 1759 to the early 1770's and from 1789 to almost the end of the eighteenth century."
and the complete railway system following much later with the first one being   "built in Great Britain to use steam locomotives was the Stockton and Darlington, opened in 1825.  It used a steam locomotive built by George Stephenson and was practical only for hauling minerals. The Liverpool and Manchester Railway, which opened in 1830, was the first modern railroad."  
       You can't, realistically, expect to resurrect a gang of Navvies ("The word 'navvy' came from the 'navigators' who built the first navigation canals in the 18th century, at the very dawn of the Industrial Revolution") just to move/re-dig an entire section of Canal to site a Railway - SO - you cut a hole in the Rail Bridge to accommodate the Lock gate Balance beam - thus.