Complex sentence: On his return he set up in medical practice at Augsburg, where his father had been transferred; but in a few months he found an opening for an academic career, on being appointed prosector at Erlangen.
Split into simpler sentences: On his return he set up in medical practice at Augsburg, where his father had been transferred. A few months later he found an opening for an academic career when he was appointed prosector at Erlangen.