Complex sentence: On 29 September that year he was promoted to major for his conduct at the Battle of Maciejowice and he also fought at the storming of Praga (a suburb of Warsaw), taking on a battery of 21 guns.
Split into simpler sentences: On 29 September that year he was promoted to major for his conduct at Maciejowice. He also fought at the storming of Prague, taking on a battery of 21 guns.