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The ''Briton'' class was a group of three wooden screw corvettes built for the Royal Navy in the late 1860s. All three ships of the class only served overseas during their brief service lives. Between them, they were assigned to the China, East Indies, African, North American, and the Pacific Stations. All three were regarded as obsolete 15 years after they were completed, and they were sold in 1886–87. ==Design and description== The ''Briton''-class corvettes were designed by Sir Edward Reed, the Director of Naval Construction, as lengthened versions of the s.〔 Like the smaller ships, they had a ram-style bow to reduce weight forward by elimination of the knee above the stem. Similarly, he shortened the counter at the stern to save weight.〔Ballard, pp. 81–82〕 The ships were long between perpendiculars and had a beam of . Forward, the ships had a draught of , but aft they drew . They displaced from and had a burthen of 1,322 tons.〔 The hull was built entirely from wood except for iron crossbeams.〔Ballard, p. 83〕 Their crew consisted of 220 officers and enlisted men.〔 Two different types of engines and boilers were used with this class. HMS ''Druid'', the first ship completed, had a two-cylinder horizontal steam engine driving a single propeller.〔 Four rectangular boilers provided steam to the engine at a working pressure of . The engine produced a total of which gave her a maximum speed of about during sea trials.〔 In contrast, the two later ships had a two-cylinder horizontal compound expansion steam engine, driving a single 15-foot or propeller.〔 Six cylindrical boilers provided steam to the engines at a working pressure of . The engines produced between which gave the two ships a maximum speed over .〔 ''Briton'' and ''Thetis'' carried of coal, while ''Druid'' carried an additional . Although no information is available on their range, Admiral G. A. Ballard estimated that ''Druid'' had only about two-thirds the range of her sisters, despite the additional coal that she carried, due to the greater efficiency of the compound expansion engines.〔Ballard, p. 90〕 The class was ship rigged and had a sail area of .〔 The lower masts were made of iron, but the other masts were wood.〔Ballard, p. 91〕 The ships were poor sailors and their best speed under sail alone was about . Ballard attributed their poor performance under sail to the drag of the propeller, which could neither be hoisted out of the water, nor feathered. He also attributed their sluggish steering under sail to interference with the flow of water to the rudder by the fixed propeller.〔Ballard, pp. 90–91〕 The first two ships were re-rigged as barques after their first commission.〔 The first two ships were initially armed with a mix of 7-inch and 64-pounder 71 cwt〔"cwt" is the abbreviation for hundredweight, 64 cwt referring to the weight of the gun.〕 rifled muzzle-loading guns. The eight 64-pounder guns were mounted on the broadside while the two guns were mounted on the forecastle and poop as chase guns.〔 The 16-calibre 7-inch gun weighed and fired a shell. It was credited with the nominal ability to penetrate armour.〔Chesneau & Kolesnik, p. 6〕 After the completion of their first commissions, the two ships were rearmed with a total of fourteen lighter 64-cwt 64-pounder guns, two of which replaced the 7-inch guns as chase guns. ''Thetis'', the last ship completed, was given this armament from the beginning.〔Ballard, p. 89〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Briton-class corvette」の詳細全文を読む スポンサード リンク
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