The Rational Almanac

Moses Cotsworth's workings on the International Fixed Calendar


Moses Bruine Cotsworth


Cotsworth, Acomb, York, 1905
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Printing Details

Undated, c1905. Assumed first edition. Hardback, bound in the original blue cloth with gilt titling and design to spine and both boards. 24.5 × 9.5cm, 16, 64, 16, 1–154, 154a-154p, 155–473pp. There is no title page with this copy, and it seems some copies have them, some don't.

A rather bizarre book by Moses Bruine Cotsworth, the pagination indicates that the parts were printed at different times before being published as this book. It is Cotsworth's ideas of an International Fixed Calendar which divides the solar year into 13 months of 28 days each (it keeps the twelve months but adds one called Sol between June and July). It is therefore a perennial calendar, with every date fixed to the same weekday every year. Cotsworth began work on the International Fixed Calendar after working for the accounts department of the North Eastern Railway Company and found that his accounting work was greatly complicated by the fact that months did not divide evenly into weeks. The book has several illustrations throughout.


This copy is in good condition for age, with some light rubbing to the corners and spine ends, and some wearing off to the gilt titling. A previous owner has made several pencil marks to the margins but the text remains clear.


Please note: Due to the recent price rise from USPS, we will be putting our postage rates to USA up for which we apologise but have no choice.



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