On 9 December 1915 at Souain, a former battlefield with rough terrain and trenches, and in the presence of General Philippe Pétain, a prototype armoured vehicle motorized with a Baby Holt caterpillar was successfully tested.  It is also known for the Souain corporals affair, 17 March 1915. The village is the site of the Monument de la Légion Etrangère, an ossuary with 130 bodies of légionnaires from the 1st and 2nd Régiment Etrangers, who fell at the French offensive in Champagne, in September 1915. The monument ossuaire was erected in 1920 by William Farnsworth, father of Harvard alumni Henry Farnsworth, a young American university student who had enlisted in the French Foreign Legion on 5 January 1915 and was killed 28 September 1915.
^Armoured fighting vehicles of the world Duncan Crow 1970 p.68 "On December 9, 1915, the Baby Holt, modified with a mock-up armoured driving position ... was demonstrated on a crosscountry course at Souain"
^Alain Gougaud L'Aube de la Gloire, Les Autos-Mitrailleuses et les Chars Français pendant la Grande Guerre, 1987, Musée des Blindés, ISBN 2-904255-02-8, p.111
^Edwin Morse The Vanguard Of American Volunteers In The Fighting Lines 1782893016 2014 "... Memorial Library at Harvard, a large room for the leisurely reading of such standard books as Henry Farnsworth loved, was handsomely supplied with books, pictures and furniture by Mr. and Mrs. William Farnsworth, in memory of their son"
^Harvard Alumni Bulletin - Volume 23 - Page 401 1920 Through the Farnsworth Room in the Widener Library Building his name is already linked, most fittingly, with the daily life of Harvard College. The new memorial in France has a significance and suggestion (if which all Americans may well take note. When Henry Farnsworth and other adventurous spirits among our younger countrymen threw themselves into the European war on the side of the Allies, ..