CORMONTAINGNE, LOUIS DE (c. French military engineer, was born at Strasbourg. He was present as a volunteer at the sieges of Freiburg and Landau in the later years of the War of the Spanish Succession, and in 1715 he entered the engineers. After being stationed for some years at Strasbourg he became captain, and was put in charge (at first in a subor dinate capacity, and subsequently as chief engineer) of the new works, Forts Moselle and Bellecroix, at Metz, which he built ac cording to his own system of fortification. He was present at the siege of Philipsburg in 1733, and took part in most of the sieges in the Low Countries during the War of the Austrian Succession. His Architecture militaire, written in 1714, was long kept secret by order of the authorities, but, an unauthorized edition having appeared at The Hague in 174i, he himself prepared another version called Premier memoire sur la fortification, which from 1741 onwards was followed by others. His ideas are closely mod elled on those of Vauban (q.v.) . It was not until 20 years after his death that his system became widely known. Fourcroy de Rainecourt, then chief of engineers, searching the archives for valuable matter, chose the numerous memoirs of Cormontaingne for publication amongst engineer officers in 1776. The Oeuvres posthumes de Cormontaingne (18o6–o9) were edited by Four croy and La Fitte de Clave.