1. Eight hundred words dated 2 April 1953.
2. Sketches, a letter, and an essay – by two gentlemen read on 1 July 1858.
3. An argument on BBC’s Third Programme on 28 March 1949.
4. A presentation in Germany on 6 January 1912 – though admittedly based on earlier work including a comment by one of the gentlemen above.
5. A diagram sketched by a Russian teacher for a textbook and presented on 6 March 1869.
6. A British magazine article on 17 March 1960.
7. A disputed flower of Kent transported (theoretically) into space and described (mathematically) in a manuscript of 28 April 1686.
8. The results of clever and accurate Lancashire brewery technology explained in Cambridge in 1845 and Oxford 1847 (with all that beer around you cannot expect the exact date, and in any case something can be thought of one day, done another, written about on a third day, received the next, and spoken about later still!).
9. Three seen in a line on 7 January 1610 and with a fourth on the 13th.
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