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    Long by Chron - Wikipedia article
    From: David C
    Date: 2020 Aug 16, 20:07 -0700

    During today's "Office Hours" session I commented that the Wikipedia articles about  lon by chron needed to  be re-written. Frank suggested that I put the link online because one of the  list members edits wikipedia articles.

    https://en.wikipedia.org/wiki/Longitude_by_chronometer

    I have just had another look at the article and my concern is no so much the content but the confusing manner in which the information is given. For example the introduction is almost a history of navigation rather than stating what Lon by Chron is....."Lon by Chron (British) aka Time Sight (US) involves measuring the altitude of the sun with a sextant and noting time on a chonometer. From the observed alrtitude, the declinaton of the sun (from an almanac) and the DR latitude, local apparant time can be calculated and hence longitude. The closer the sun is to the prime vertical the less the error caused by an incorrect DR latitude."

    (The above is OTTOMH and may or not be completely accurate but I hope you get my drift.)

    The first section in the main part of the article should be a detailed description of a time sight. In stead it is confusingly headed Noon Sight for Longitude. This section discusses double altitides which has absolutely nothing to do with long by chron.

    In summary I believe that the information on the page is correct but unfortunately it is presented in a confusing and in some case irelevant manner. I admit that I cannot get motivated to re-write it!

    P.S. Frank's cat and my cat appear to have come from the  same litter.

       
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