Born in Basel in 1759 (17 October), the son of Johann (II). 1780 assistant to Daniel in experimental physics
He graduated in Jurisprudence in 1778 but also studied Maths and Physics. In 1782, he applied for Daniel's former chair but was unsuccessful.
He became secretary to an imperial representative in Venice
In 1786 he went to Petersburg, to the Academy of Science (Fuss recommended him to Dashkoff) and in 1788 became ordentlich academy member for mathematics.
He married one of Euler's granddaughters, Charlotte.
At thirty years of age, he drowned in the Neva.