ALrrivei two mails from Tlandtrs, and one from Holland. From the London Gazette, Auguft 23. King of Pruffta's head quarters at Dahvitz, Auguft z. ON t'ne aid of lait month, his P ruffian Maje- fty fixed his camp at Leitbnitz, about feven in the morning .. and, on the 2.9 th in th