 Complete the following phrase:  Towards the end of 1777 he was appointed to the 50-gun , flagship of Rear-Admiral Sir Peter Parker. On 26 December 1777 Parker sailed from Portsmouth with a squadron of ships, carrying troops under the command of Earl Cornwallis, to launch an attack on Charleston, South Carolina. The squadron arrived off Cape Fear in May, and was joined by General Henry Clinton and his troops. The combined force advanced upriver until reaching the strongly fortified Sullivans Island. In the 