[161] The details of these trials against iron plate will be found in Sir Howard Douglas’ _Naval Gunnery_, third and subsequent editions. [162] The rapid construction of over two hundred gunboats and their steam machinery revealed the enormous industrial capacity of this country, and constituted a feat of which the whole nation was rightly proud. For instance of successful organization, Messrs. Penn of Greenwich contracted to build eighty sets of main engines in three months--a proposition ridiculed as impossible. By the rapid distribution of duplicate patterns throughout the country the resources of all the greatest firms were utilized, and the contract was fulfilled almost to the day! Some seven or eight years later, when the building of ironclads was being debated in parliament, the government was able to recall this achievement as an argument for not building too many ships of a new and probably transitional type. If we liked, it was said, we could soon produce a fleet of ironclads far greater than all the other Powers of Europe besides. [163] J. Scott Russell: _The Fleet of the Future: Iron or Wood?_ 1861. [164] Reed: _Our Ironclad Ships_. [165] Boynton: _The Navies of England, France, America, and Russia._ New York, ’65. [166] Colomb: _Memoirs of Sir Cooper Key_. [167] Colomb: _Memoirs of Sir Cooper Key_. [168] In parenthesis, for she is of no special interest as a type, we may note here the _Temeraire_, built at Chatham and completed in 1877: a compromise between the central-battery and the turret ship. Generally like the _Alexandra_ in disposition of armament, she carried in addition, in order to give all-round fire, two open barbettes, one at each end of the upper deck, each containing a 25-ton gun hydraulically operated. [169] The freedom of the _Royal Sovereign’s_ turrets from any liability to jam was demonstrated at Portsmouth by subjecting them to the impact of projectiles fired from the 12-ton guns of the _Bellerophon_. [170] Colomb: _Memoirs of Sir Cooper Key_. [171] Hitherto the torpedo had been used in warfare only in the form of a stationary mine, or motion had been given to it either by letting it drift on a tide or by attaching it rigidly to the bow of a vessel. After the American Civil War, in which conflict three-fourths of the ships disabled or destroyed were so disposed of by torpedoes, efforts were made to give motion to it, either by towing or by self-propulsion. In ’69 Commander Harvey, R.N., brought to the notice of the Admiralty his invention of a torpedo or sea kite which was so shaped that, when launched from the deck of a steamer and towed by a wire, it diverged from the steamer’s track and stood away at an angle of 45°. It could be exploded either electrically or by contact. The possibilities of this weapon were illustrated in a volume published in ’71, one picture of which showed luridly “an ironclad fleet surprised at sea by a squadron of torpedo craft armed with Harvey’s sea torpedoes.”