Ship service was an onerous duty and the five original head ports enlisted the help of neighbouring towns and villages, which were known as members or limbs, to help them fulfil their quotas of ships and crew. Some of the limbs were merely small villages and hamlets and these non-corporate members negotiated directly, with their head port, to provide ships and men, in return for the right to share in the privileges granted to the head port. Other limbs were more substantial communities and were granted their own charters by the Crown, thus becoming corporate members. At one time, there were 23 limbs covering an extensive area from Seaford, in the west, to Brightlingsea on the Essex coast. Rye and Winchelsea were, originally, corporate members of Hastings but, as the harbour at Hastings silted up, the port found it difficult to fulfil its quota and relied increasingly on the assistance of its major limbs.