Can anyone with access to the original literature shed light on the
period(s) over which Alexander Buchan based his analysis?

The Meteorological Glossary (var. ed), mentions 'over 50 years', but in
works by Lamb, Goldie etc., the period 1857-1866 is listed (the original
work, I believe, was published in 1867), with ".... account being taken
of certain records back to 1795".
(Don't worry: I'm not trying to resurrect these spells for any sinister
or populist purpose! Just trying to find out the truth behind the
analysis.)

Martin.

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