![]() This dry dock currently holds First World War monitor HMS M33. The first early modern European and oldest surviving dry dock still in use was commissioned by Henry VII of England at HMNB Portsmouth in 1495 (see Tudor navy). Finally the beams and pillars were taken away, and the whole basin covered over with a great roof so as to form a hangar in which the ships could be protected from the elements and avoid the damage caused by undue exposure. When the repairs were complete, the water was let in again, so that the ships were afloat once more (and could leave the dock). Then (breach now being closed) the water was pumped out by wheels so that the ships rested quite in the air. Then (a breach was made) so that the basin quickly filled with water, after which the ships were towed in above the beams. A large basin was excavated at the north end of the Chin-ming Lake capable of containing the dragon ships, and in it heavy crosswise beams were laid down upon a foundation of pillars. So in the Hsi-Ning reign period (+1068 to +1077) a palace official Huang Huai-Hsin suggested a plan. After many years, their hulls decayed and needed repairs, but the work was impossible as long as they were afloat. ![]() The upper works included several decks with palatial cabins and saloons, containing thrones and couches all ready for imperial tours of inspection. +965) the two Che provinces (now Chekiang and southern Chiangsu) presented (to the throne) two dragon ships each more than 200 ft. In 1088, Song Dynasty scientist and statesman Shen Kuo (1031–1095) wrote in his Dream Pool Essays:Īt the beginning of the dynasty (c. ![]() The use of dry docks in China goes at least as far back as the 10th century A.D. In Roman times, a shipyard at Narni, which is still studied, may have served as a dry dock. It has been calculated that a dock for a vessel of such a size might have had a volume of 750,000 gallons of water. And in the trench he built props of solid stone five cubits deep, and across them he laid beams crosswise, running the laces whole width of the trench, at four cubits' distance from one another and then making a channel from the sea he filled all the space which he had excavated with water, out of which he easily brought the ship by the aid of whatever men happened to be at hand then closing the entrance which had been originally made, he drained the water off again by means of engines (organois) and when this had been done the vessel rested securely on the before-mentioned cross-beams. īut after that a Phoenician devised a new method of launching it (the Tessarakonteres), having dug a trench under it, equal to the ship itself in length, which he dug close to the harbour. The Greek author Athenaeus of Naucratis (V 204c-d) reports something that may have been a dry dock in Ptolemaic Egypt in the reign of Ptolemy IV Philopator (221-204 BC) on the occasion of the launch of the enormous Tessarakonteres rowing ship. Dry docks are used for the construction, maintenance, and repair of ships, boats, and other watercraft. Navy submarine USS Greeneville in a graving dock A US Navy littoral combat ship in drydock, NASSCO 2012Ī dry dock (sometimes drydock or dry-dock) is a narrow basin or vessel that can be flooded to allow a load to be floated in, then drained to allow that load to come to rest on a dry platform. Basin drained to allow work on a vessel U.S.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |