Definition of "Chats"

I think it is a libel, for I have yet to learn that West Country sailor-men are fonder of their victuals than those from 'Pompey' (Portsmouth), or 'Chats' (Chatham), or than Scotsmen, Irishmen, or Welshmen.

1918, Chambers's Journal, volume 95, page 393

He leaned half his body out of the carriage window as we slowly pulled over the timber baulks of the rebuilt bridges, and shouted 'Up the workers!' until a Petty Officer in the next compartment also leaned out and told him, 'Shit in it, you bloody Bolshie, or I'll have your cap as soon as we get to Chats.' […] Once inside the prison-like walls of Chatham barracks we were all marched into the drafting office […]

1997, Tristan Jones, Heart of Oak, page 132