Kearsley's Traveller's Entertaining Guide through Great Britain (1803):
Deal , a large seaport, defended by a castle built by Henry VIII; and near it are two others. Between this place and the Goodwin sands are the Downs. It is called Dola by Julius Ceasar, who is supposed to have landed here in his second descent upon Britain. A ridge of cliffs runs along the coast from hence to Dover, which abound with samphire. The number of its inhabitants, by the return made in 1801 to parliament was 5420.
Inns: Three Kings, Royal Exchange.
Use the "Show me" link to locate Deal on the map. You may need to scroll down to see Deal highlighted.