A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David C
Date: 2018 Dec 18, 18:04 -0800
You seem to infer on Dec 16 that the use of the expression “longitude by chronometer” tailed off after the 19th century, and is somehow wrong. Attached is a page from my 1956 Nories, and a page from my 1985 Reed’s Nautical Almanac, this latter page title reproduced exactly in the dozen or so annual Reed’s almanacs I have to hand, going up to at least 1992. The methodology is evident in these attachments.
Thanks for posting the page from Nories. I have several copies of Norie and wondered why I had not seen that explanation before. The answer is that I do not have a copy of the 1956 edition. The information is given in other editions but not in such a clear manner. I must keep a look out for the 1956 edition of Norie.
In 1918 and 1944 the phrase "longitude by chronometer problem" was used. In 1970 and 1983 the phrase used was "finding the computed longitude when establishing the position line by the chronometer method". Even if we accept that all observations result in a position line I believe that it is legitmate to refer to a "chronometer" method - at least, in British practice.