At 11:16 AM 10/12/2005 +0100, Frank Evans wrote: >My question is: Was this, like Richardson's appendix in Mrs. Gatty's >book, a first appearance of an equation of time line? Can anyone supply >earlier earlier examples of such a line on dials either in the UK or >elsewhere?
Frank and others, I think the lack of equation-of-time indicators on dials before the mid-1800s has a simple explanation: Sundial time was considered CORRECT, and the mean solar time shown by clocks WRONG (or, at least, a mere approximation). For example, I have several English almanacs for the year 1714. One of them is The Ladies Diary: or, the Woman's ALMANACK. Next to many dates throughout the year, it has phrases such as: "Watches 3 minutes, 49 seconds too fast" "Watches have gained of the Sun 2 minutes in 8 days" "Watches will be 14 min. slower than a good Sun-dial" Another one, John Wing's Almanack, says on the cover that it contains "an Equation Table, for the rectifying Pendulum Clocks and Watches." (Unfortunately, that particular table is missing from my copy.) -- Roger -
