8-inch shell gun added, though all were still smooth-bore guns. Four early breech-loading RBL 40 pounder Armstrong guns mounted on field carriages had replaced the earlier movable guns in 1862. The focus of the Army's fortification efforts was initially on the outer forts at Coalhouse Point, Cliffe and Shornemead, and it was not until January 1868 that instructions were issued by the War Office to reconstruct Tilbury and New Tavern Forts. The existing magazines and ramparts were demolished and new brick emplacements were built, on which were mounted ten 9-inch and one 12-inch RML guns capable of ranges of up to . Seven of the emplacements were protected by iron shields. The ramparts were extensively remodelled to accommodate new magazines, which were connected via lift shafts to serving rooms adjoining the emplacements. Colonel (later General) Charles George Gordon, who was to become famous for his death in the Siege of Khartoum in 1885, lived in Fort House in the grounds of the fort between 1865 and 1871 while he was overseeing the project. 20th century The fort had lost much of its importance by the turn of the 20th century. Advances in naval firepower meant that the principal line of defence for the Thames had been moved downriver to the batteries at Grain and Shoeburyness, where bigger guns with a longer range could control the entire estuary mouth. The old RML guns were now obsolete, while the emplacements provided little protection against modern naval artillery. A War Office report of 1887-8 commented that New Tavern Fort's "guns are crowded, and behind weak parapets; the parapets should be revised, and the number of guns reduced, so that they may be more effectively mounted." Proposals were advanced for this to be done and for the range of the guns to be extended by remounting them on modified carriages, but neither of these improvements were implemented. In 1905 the RML emplacements were replaced with two concrete pits for a pair of 6-inch breech-loading guns with a range of , with separate magazines constructed to support them. They were only emplaced for a few years and the fort was disarmed before the outbreak of the First World War in 1914 and was rearmed in 1930 with a pair of replacement 6-inch guns, used to train the Territorial Army's Gravesend battery. At the same time, the Gravesend Corporation purchased the interior of the fort. The