NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: The spirit of Marcq St.-Hilaire
From: Herbert Prinz
Date: 2001 Jul 11, 10:54 PM
From: Herbert Prinz
Date: 2001 Jul 11, 10:54 PM
nigel_gardner wrote: > Perhaps Herbert could quote his primary sources so that we could read them > for ourselves. My primary source of information on the subject of 'New Navigation' is Yvon Villarceau and Aved de Magnac, "Nouvelle Navigation Astronomique", Paris, Gauthier-Villars, 1877. Formally, this book is the second part of the second section of a 'Traite de navigation". The first section is on dead reckoning, the first part of the second section on "ancient" methods of astronavigation (including lunars) and the third section on coastal navigation. However, chronologically, it was the first one of the series to be published, which is an indication for the priority and importance that the authors gave it. Villarceaux was astronomer at the Paris observatory. He gave the New Navigation its mathematically sound fundament. Lieutenant de Magnac, a French Navy officer dealt with its practical aspects. In a footnote to article 91 on p.104 of his part of the book, De Magnac credits St-Hilaire with the "introduction of the consideration of the point rapproche" and mentions that it has in fact been in use since 1874 on board of the school ship La Renommee. In article 114, pp120-122, de Magnac explains and reviews the procedure of Marcq-Saint-Hillaire. It is from there that I took my description in my previous post. I guess the logs of La Renommee would be the true primary source. There is also a paper that Marcq St-Hilaire published in 1875 in Revue Maritime, again on the methode du point rapproche.( I have not yet been able to find a library that holds a copy. I would be grateful for any leads.) To de Magnac, the point rapproche is St-Hilaire's significant contribution to the New Navigation. By the way, even in 1877 de Magnac has still no name for that magnitude p that equals the distance between the assumed position and the point rapproche. Herbert Prinz (from 1368950/-4603950/4182550 ECEF)