dark ages book

https://www.amazon.com/Medieval-Machine-Industrial-Revolution-Middle/dp/0140045147/ref=sr_1_1?s=books

Cool book. Actually, a lot happened in the middle ages. Architecture,
engineering,  agricuture, machines, clocks, compasses, math, the
beginnings of real science.

This is well researched and well written. The author preaches a bit in
the preface and epilogue, to the effect that at the time of writing
(1977!) most everything has been invented and progress was mostly
over.

My copy was dumped by the UWE Redland library in Bristol England. It
hadn't been checked out much.