Rarely or briefly mentioned in aeronautical encyclopedias, the Swiss Alexandre Liwentaal (1868-1940) turns out to be an exceptional engineer to whom the world of aviation, among other things, owes a certain number of technological firsts, of which we did not know until to today neither the origins nor the circumstances of development. Collaborator of influential personalities such as Gaston Tissandier, Hiram Maxim, Count von Zeppelin, Walter Wellman, or independent initiator of crazy projects, Liwentaal now stands out as a precursor, mainly in ballooning and aviation (long before the Wright brothers), but also in motorization, communication or maritime transport. Thanks to this work, the versatile inventor, modest but undisputed in the ten European and North American nations where he demonstrated his ingenious spirit, thus accesses the collective aeronautical memory.