Fort Pitt next claims our attention. It stands on the high ground above the Railway Station at Chatham, just beyond Ordnance Terrace. In Charles Dickens's early days, and indeed long after, until the establishment of the magnificent Institution at Netley, Fort Pitt was the principal military Hospital in England, and was visited by Her Majesty during the Crimean War. It is still used as a hospital, and contains about two hundred and fifty beds. The interesting museum which previously existed there has been removed to Netley. From Fort Pitt we see the famous "Chatham lines," which constitute the elaborate and almost impregnable fortifications of this important military and ship-building town. The "lines" were commenced as far back as 1758, and stretch from Gillingham to Brompton, a distance of several miles, enclosing the peninsula formed by the bend of the river Medway. Forster says:-- [Illustration: Navy Pay-Office, Chatham.] "By Rochester and the Medway to the Chatham lines was a favourite walk with Charles Dickens. He would turn out of Rochester High Street through the Vines, . . . would pass round by Fort Pitt, and coming back by Frindsbury would bring himself by some cross-fields again into the high-road." The Chatham lines are locally understood as referring to a piece of ground about three or four hundred yards square, near Fort Pitt, used as an exercising-ground for the military. Chapter IV. of _Pickwick_, "describing a field day and bivouac," refers to the Chatham lines as the place where the review was held, on the third day of the visit of the Pickwickians to this neighbourhood, and which (having been relieved of the company of their quondam friend, Mr. Jingle, who had caused at least one of the party so much anxiety) they all attended, possibly at Mr. Pickwick's suggestion, as he is stated to have been "an enthusiastic admirer of the army." The programme is thus referred to:-- "The whole population of Rochester and the adjoining towns, rose from their beds at an early hour of the following morning, in a state of the utmost bustle and excitement. A grand review was to take place upon the lines. The manoeuvres of half a dozen regiments were to be inspected by the eagle eye of the commander-in-chief; temporary fortifications had been erected, the citadel was to be attacked and taken, and a mine was to be sprung."