Jean-Charles de Borda
Jean-Charles de Borda (born May 4, 1733 in Dax , Gascogne , † February 20, 1799 in Paris ) was a French mathematician and seaman .
Borda received his training at the Collège Henri-IV de La Flèche and then entered the genius corps . As early as 1756 he acquired membership of the Académie des Sciences through studies of ballistic problems . In 1757 he took part in the battle at Hastenbeck as an adjutant to Marshal Jean-Baptiste Desmarets and joined the navy the following year . Here he mainly dealt with nautical , astronomical and hydraulic problems. In 1771 he traveled with Jean-René de Verdun de la Crenne (1741-1805) and Alexandre Guy Pingré to North America to test the chronometers , while at the same time correcting the geographical longitudes and latitudes of many coastal points, islands and cliffs. The three published the results of this trip in the Voyage fait par ordre du roi en 1771 et 1772 en diverse parties de l'Europe et de l'Amerique . 2 vols. Paris (1778).
In 1774 Borda traveled to Cape Verde , the "Islands of the Green Foothills", and to West Africa on the same matter . He repeated this trip a few years later. In 1777 and 1778, Borda contributed to the success of the French armed forces in North America as major general of the naval forces . In 1782 he was caught by the English on his way back from Martinique and released on word of honor to France. Here he entered the Navy Ministry as a division chief .
In addition to services to the French navy, nautical science and shipbuilding , Borda also made a name for himself with various scientific works and inventions. Among other things, he developed a water turbine , using curved blades for the first time to reduce shock losses. He was a participant in the last French degree measurement , where he determined the size of the rulers using an ingenious method and also precisely determined the length of the seconds pendulum using a new method. We also owe him a method for measuring refraction and the invention of the reflection and repetition circles named after him (see Borda circle ). He also participated in the commission on the new weights and measures at the time. The term meter goes back to him when the definition of the original meter was legally established in the National Convention .
Borda developed, in conflict u. a. to the Marquis de Condorcet , the Borda electoral process , which is not used because of its weaknesses in politics, but is popular in competitions such as the Eurovision Song Contest .
Jean Charles Borda died in Paris on February 20, 1799.
His name is immortalized on the Eiffel Tower . The lunar crater Borda and the asteroid (175726) Borda are named after him.
He was a member of the Académie des Sciences .
Web links
- John J. O'Connor, Edmund F. Robertson : Jean-Charles de Borda. In: MacTutor History of Mathematics archive .
| personal data | |
|---|---|
| SURNAME | Borda, Jean-Charles de |
| BRIEF DESCRIPTION | French mathematician and sailor |
| DATE OF BIRTH | May 4, 1733 |
| PLACE OF BIRTH | Dax |
| DATE OF DEATH | February 20, 1799 |
| Place of death | Paris |