other preparations. Campaign British moves Although Major General Ross commanded the British troops in Chesapeake Bay, the point of attack was to be decided by Vice Admiral Cochrane, who had concentrated four ships of the line, twenty frigates and sloops of war and twenty transports carrying Ross's troops at Tangier Island. Rear Admiral Cockburn, Cochrane's second in command, favoured a quick attack on Washington, but Ross was not eager. His men had been confined aboard their transports for nearly three months, and he lacked cavalry, artillery, and transport. Ross was also wary of the U.S. Chesapeake Bay Flotilla, lurking in the Patuxent River. His first objective had to be the capture or destruction of the U.S. flotilla. Cochrane dispatched two forces to make diversions. The frigate HMS Menelaus and some small craft threatened a raid on Baltimore, while two frigates and some bomb ketches and a rocket vessel ascended the Potomac River, an expedition that resulted in the successful Raid on Alexandria. His main body proceeded into the Patuxent. Ross's troops landed at Benedict on 19 August, and began marching upstream the following day, while Cockburn proceeded up the river with ships' boats and small craft. By 21 August, Ross had reached Nottingham, and Commodore Joshua Barney was forced to destroy the gunboats and other sailing craft of the Chesapeake Bay Flotilla the next day, and retreat overland towards Washington. From Nottingham, Ross continued up the Patuxent to Upper Marlboro, from where he could threaten to advance on either Washington or Baltimore, confusing the Americans. He might have taken the capital almost unopposed had he advanced on 23 August, but instead he rested his men and organised his force. On the night of 23–24 August, at the urging of Rear Admiral Cockburn and some of the British Army officers under his own command, Ross decided to risk an attack on Washington. He had four infantry battalions, a battalion of Royal Marines, a force of about 200 men of the Corps of Colonial Marines, which was composed of locally recruited black refugees from slavery, a Congreve rocket detachment from the Royal Marines battalion, 50 Royal Sappers and Miners, 100 gunners from the Navy and 275 sailors to carry supplies. His force totaled 4,370 men, with one 6-pounder gun, two 3-pounder guns and sixty launchers, each being attached to a rocket. Rear Admiral Cockburn accompanied this force. Ross had a choice of