tJie NecessUu of Vifting Ships. £45 



and at the latter a three-decked ship, v/ere suspended in 

 like manner. This happened in December 1S02. and 

 January 1803; and the reports were so favourable, as to 

 cause directions to be given for the general adoption of these 

 blocks in his majestv's yards. This invention being 

 thought of national consequence, with respect to ships, but 

 particularly those of the navy, government has been pleased 

 to notice and reward Mr. Seppmgs for it. 



The time required to disengage each block is from one to 

 three minutes after the shores are placed : and a first-rate 

 sits on about fifty blocks. Various are the causes for 

 which a ship may be required to be cleared from her blocks, 

 viz. to shift the main keel ; to add additional faslt keel ; to 

 repair defects ; to caulk the garboard seams, scarples of the 

 keel, &c. Imperfections in the false keel, which are so 

 very injurious to the cables, can, in the largest ship, be 

 remedied in a few hours by tliis invention, without adding 

 an additional shore, by taking away blocks forward, amid- 

 ships, and abaft, at the same time; and, when the keel is 

 repaired in the wake of those blocks, by returning them 

 into their places, and then by taking out the next, and so 

 on in succession. The blocks can be replaced in their ori- 

 ginal situations, by the application of the wheel battering- 

 rams to the wedges, the power of which is so very great, 

 that the weight of the ship can be taken from the shores 

 that were placed to sustain her. There were one hundred 

 and six ships of different classes, lifted at Plymouth dock- 

 yard, from the 1st of January 1798 to the 31st of Decem- 

 ber 1800; and, had the operation of lifting taken less time, 

 the number would have been very considerably increased; 

 for the saving; of a day is very frequently the cause of saving 

 a spring tide, which iDakes the difi'erence of a foitnight. 

 The importance of this expedition, in time of war, cannot 

 be sufficiently estiaiiated. 



This invention may be applied with great advantage, 

 whenever it is necessary to erect shores, to support any 

 great weights, as, for instance, to prop up a building during 

 tiie repair of ils foundation, &c. Captain W^ells, of his 

 majesty's ship Glory, of 98 guns, used wedges of Mr. Sep- 

 pings's invention for a lid of a top-gailant mast of that 

 ship. In 1803, the top-gallant masts of the Defence, of 

 74 guns, were fitted on this princii'le by Mr. Seppings : 

 and, from repeated trials, since she 1k.s been cruizing in the 

 North Sea, the wedge fids have been found in every respect 

 (o answer. 



t^ul it is Mr. Seppings's wish that it should be undcr- 

 Q 3 stood, 



