A Psalm for Falconer is the fourth in the William Falconer historical series by Ian Morson. I started reading this series back when I had periodic business trips to the UK and would pick up pounds (or kilos) of historical mysteries in DTB to haul home, mostly titles that were unavailable or really hard to find in the US. E-books are so much easier

, but Morson's titles only very very rarely go on sale, so I'm happy to see this one drop to $2.48 at Kindle US.
link:
https://www.amazon.com/dp/B0087FDD54