NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: The Old vs. The New
From: Frank Reed CT
Date: 2004 Jan 21, 22:06 EST
From: Frank Reed CT
Date: 2004 Jan 21, 22:06 EST
Chuck T wrote:
"I have the impression from my reading that the sight reduction method of choice as late as WW II was the Cosine-Haversine method. Hosmer (1926) mentions the use of tables, but only as an afterthought. Dutton's (1942) describes H.O. 208 (Dreisonstok), H.O. 211
(Ageton), and H.O. 214, but in less detail and only after presenting the Cosine-Haversine method. The implied message as I read it is, "Here are some new methods that may be worthy of your attention some day." As Dan Allen has pointed out, the 1943 Bowditch
took a similar stance."
Some publications were more conservative, of course, and it also depends on the very rapid rate of change during the war. I've just read the preface to the Second Edition of Mixter's excellent "Primer of Navigation" which was published in 1943. Among the changes from the 1940 edition, he mentions much greater coverage of various tabular methods (too many). When he gets into the discussion of sight reduction in chapter 26, he begins with a brief account of the "new navigation" and the "old navigation" and mentions that time sights are still practiced in the US Merchant Marine.
A bit further on, Mixter writes:
"New methods to faciliate finding the computed altitude and azimuth were developed as the use of Sumner lines determined by altitude differences increased. The tables of Aquino (1910) and Ogura (1920) and the bulky H.O. 203 (1923) marked steps in advance. "
Mixter writes that:
"the methods most often taught in 1930 included:
Marcq St.-Hilaire or cosine-haversine: Strictly speaking, all the methods of the new navigation [...are of this type].
In the more common use of the term, a navigator saying he uses Marcq St.-Hilaire means that he computes the altitude by the cosine-haversine formula of St.-Hilaire. This gives the intercept but the azimuth must be taken from azimuth tables or found by an additional computation.
This method came into general use in the Navy about 1910, was taught during World War I, and today remains in common use by navigators so trained. [...] it is somewhat long and is being supplanted by new methods which give both altitude and azimuth with less work."
It sounds as if he's saying that it is his belief that "cosine-haversine" is already old-fashioned.
Mixter then goes on to describe two tabular methods which he says have already faded in popularity:
" Line of Position Book, Weems, 1927, is a small book of Japanese tables by Ogura... [...] received considerable publicity for air work and was used by Colonel Lindbergh. [...] Although not now in general use, this thin red book marked a step in Weem's bold and successful efforts to simplify navigation.
H.O. 208, 1928, [...] remain[s] popular in the Navy and the Merchant Marine and with other navigators who adopted this method when first published."
Before getting into details on the latest tables, Mixter writes:
"Since 1930 several important new tables for altitude and azimuth have been published [...] the older methods should not be taught to present-day students."
So that's a pretty solid opinion direct from war-time New York in 1943!
Mixter provides a longer introduction to H.O. 211 (1932), Ageton's "A.A.A." tables (1942), and H.O. 214 (which seems to be his favorite).
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
"I have the impression from my reading that the sight reduction method of choice as late as WW II was the Cosine-Haversine method. Hosmer (1926) mentions the use of tables, but only as an afterthought. Dutton's (1942) describes H.O. 208 (Dreisonstok), H.O. 211
(Ageton), and H.O. 214, but in less detail and only after presenting the Cosine-Haversine method. The implied message as I read it is, "Here are some new methods that may be worthy of your attention some day." As Dan Allen has pointed out, the 1943 Bowditch
took a similar stance."
Some publications were more conservative, of course, and it also depends on the very rapid rate of change during the war. I've just read the preface to the Second Edition of Mixter's excellent "Primer of Navigation" which was published in 1943. Among the changes from the 1940 edition, he mentions much greater coverage of various tabular methods (too many). When he gets into the discussion of sight reduction in chapter 26, he begins with a brief account of the "new navigation" and the "old navigation" and mentions that time sights are still practiced in the US Merchant Marine.
A bit further on, Mixter writes:
"New methods to faciliate finding the computed altitude and azimuth were developed as the use of Sumner lines determined by altitude differences increased. The tables of Aquino (1910) and Ogura (1920) and the bulky H.O. 203 (1923) marked steps in advance. "
Mixter writes that:
"the methods most often taught in 1930 included:
Marcq St.-Hilaire or cosine-haversine: Strictly speaking, all the methods of the new navigation [...are of this type].
In the more common use of the term, a navigator saying he uses Marcq St.-Hilaire means that he computes the altitude by the cosine-haversine formula of St.-Hilaire. This gives the intercept but the azimuth must be taken from azimuth tables or found by an additional computation.
This method came into general use in the Navy about 1910, was taught during World War I, and today remains in common use by navigators so trained. [...] it is somewhat long and is being supplanted by new methods which give both altitude and azimuth with less work."
It sounds as if he's saying that it is his belief that "cosine-haversine" is already old-fashioned.
Mixter then goes on to describe two tabular methods which he says have already faded in popularity:
" Line of Position Book, Weems, 1927, is a small book of Japanese tables by Ogura... [...] received considerable publicity for air work and was used by Colonel Lindbergh. [...] Although not now in general use, this thin red book marked a step in Weem's bold and successful efforts to simplify navigation.
H.O. 208, 1928, [...] remain[s] popular in the Navy and the Merchant Marine and with other navigators who adopted this method when first published."
Before getting into details on the latest tables, Mixter writes:
"Since 1930 several important new tables for altitude and azimuth have been published [...] the older methods should not be taught to present-day students."
So that's a pretty solid opinion direct from war-time New York in 1943!
Mixter provides a longer introduction to H.O. 211 (1932), Ageton's "A.A.A." tables (1942), and H.O. 214 (which seems to be his favorite).
Frank E. Reed
[X] Mystic, Connecticut
[ ] Chicago, Illinois
