They knew how to build things in those days", exclaims George Ballinger, head of engineering at the Canal & River Trust, as we stand next to the massive bulk of the embankment carrying the Macclesfield Canal high above the town of Bollington. He's being ironic. When it came to understanding the science and engineering of how to build embankments that would stay up, it appears that they knew pretty damn close to zero. Even as late as the 1820s, when this latecomer of the canal era was under construction, building earthworks seems at times to still have been very much a case of trial and error. If it stayed up, fine. If it didn't, they rebuilt it. And at times they didn't even seem to learn from their errors. Take this extract from a letter from engineer William Crosley to the canal company... "A slip has taken place in this embankment, which has not only retarded the work, but has injured the masonry of the Culvert..." Like any decent engineer, he's keen to find out the reason ...
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