This shows a significant change from historic salt works hugging the canal, to the development of much larger chemical works industry on the south side of the town. The importance of the Railway becomes considerably more essential for the economical distribution of salt. 

Note the velvet works shown on the 1874-5 map has changed to a fustian works; the silk factory had closed and therefore velvet was no-longer easy to produce, so fustian was manufactured instead. Both velvet and fustian needed salt in their manufacture and finishing.