There are some fascinating conversations on Facebook. One I’ve been following this morning is about civil engineering, having started off on the subject of Chat Moss but drifted, as these things do.
Quote “… this led to a new engineer doing a survey of Standedge tunnel, whereupon it was discovered that the two workings would miss each other be several feet, one being higher than the other.”
Taken out of context those “several feet” might not seem much of a problem. The fact that one was higher than the other could have been solved quite easily by variation in gradient, if it was a railway tunnel, but the quote is referring to the canal tunnel!