Ferdinand Graf von Zeppelin was a cavalry officer. After the maneuvers of 1890 he left active military service as a lieutenant general and began to work on a rigid airship. In 1894 an expert commission appointed by Kaiser Wilhelm II declared the project unworkable. Its members included the physicist Hermann von Helmholtz. After two sessions it advised the Prussian war ministry not to support the project. From 1895 people called Zeppelin a fool, and some laughed at him in the street. After a series of accidents with his airships he was known as der Narr vom Bodensee, the fool of Lake Constance. The Kaiser called him den Dümmsten aller Süddeutschen, the dumbest of all South Germans. In 1896 Zeppelin joined the Association of German Engineers, the VDI. On 2 July 1900 his first airship, LZ 1, rose from Manzell on Lake Constance.