To Thomas Jefferson from Jacques Joseph Ducarne de Blangy, 3 July 1801
From Jacques Joseph Ducarne de Blangy
Paris, 3 July 1801. The United States, having several rivers and being bound on one side by the sea, may be interested in measures that could save the lives of ships’ crews and help to recover merchandise from shipwrecks close to shore. He was motivated to begin experimenting in these methods after he read about an incident in which 25 people perished within sight of land. He has succeeded in shooting a lifeline several hundred yards, and encloses a small printed tract that describes his work. One obstacle that he has had to overcome is the clannishness that Rousseau considered to be the greatest enemy to the sciences. In Ducarne de Blangy’s case, his work has been dismissed because he is not an artillery officer but a civilian, and one of provincial origin. He knows, though, that his advancements will save thousands of lives each year. He urges TJ to have a trial made using a kite to carry a line between ship and shore on a stormy day. Ducarne de Blangy is confident that the method will work, but his more than 70 years of age and other circumstances have prevented him from proving it himself by experiment. He points out that the method of shooting a line by rocket or cannon can also be employed as an aid to help cross large rivers such as those found in the United States. When one uses a rocket for that purpose, a barbed projectile, which he illustrates, is the best means of securing a line to the far shore of a river. He also draws two ways of arranging the rope before launching a line to a ship with a mortar. He is as proud of those developments in specific techniques as he is of his basic concept itself. He also encloses a manuscript summary of the methods contained in the printed work.
RC (DLC); 6 p.; in French, dated 14 Messidor Year 9; at head of text: “Monsieur Le president.” Recorded in SJL as received 4 Nov. 1801. Enclosures: (1) Explanation of Enclosure No. 2, summarizing ways of reaching a ship in distress with a rope propelled from shore by mortar, rocket, or kite (MS in same; in French, in Ducarne de Blangy’s hand; at head of text: “á m. Le president des etats unis” and “Résumé Des Moyens Détaillés Dans L’ouvrage imprimé Ci joint”—that is, “summary of means detailed in the enclosed printed work”). (2) Ducarne de Blangy, A la Nation française, aux Consuls de la République, à toutes les nations maritimes du globe et à toutes les sociétés savantes de l’Europe, ou moyen propres à sauver les équipages d’une partie des vaisseaux qui viennent échouer et périr à la côte (Paris, 1801); see Catalogue général des livres imprimés de la Bibliothèque nationale. Auteurs, 231 vols. (Paris, 1897–1981), 42:1081–2.
Jacques Joseph Ducarne de Blangy (1728-c. 1803) was a French agronomist and inventor who had published tracts on such topics as methods of reaping grain during rainy years and the “economic education” of bees. He began his experiments with rockets and methods of getting lifelines to ships in danger in 1791 (, 1137).