Catholic Encyclopedia (1913)/Lawrence Hengler
Catholic priest and the inventor of the horizontal pendulum, b. at Reichenhofen, Würtemberg, 3 Feb., 1806; d. at Tigerfeld, 1858. At the age of fourteen he entered the Latin School of Leutkirch and attended successively those of Ehingen and Tübingen. In 1828 he studied mathematics and astronomy at Munich. It was at this place, and while a pupil of Gruithuisen, that he invented the horizontal pendulum, which at present is the basis of more than half the seismographs in use the world over. In 1832 he published this invention in the "Analecta" of Gruithuisen, together with some experiments he had made. In 1835 he was ordained in Rottenburg and was pastor of Tigerfeld at the time of his death. He left a very perfect and elaborate telescope unfinished.
In modern publications the horizontal pendulum is mostly accredited to Zollner (1869), sometimes to Perrot (1862), but illustrated articles with observations in the "Analecta" of Gruithuisen, vol.I, and in Dingler's "Polytechnic Journal", 1832, secure for Hengler the indisputable right of priority. A full description of the pendulum and its history may be found in Zollner's "Abhandlungen", vol. IV, and also in Poggendorf's "Annals", vol. CL.
F. L. ODENBACH