 Complete the following phrase:  At the start of the War of the Fourth Coalition, Marcognet commanded a brigade in Gaspard Amédée Gardannes division of Marshal Michel Neys VI Corps. The brigade consisted of the 1st and 2nd Battalions of the 25th Light Infantry Regiment. He led his troops at the Battle of Jena on 14 June 1806 and at the Siege of Magdeburg from 22 October to 11 November. Neys corps arrived at the 