MEMOIR OF HER MAJESTY'S STEAM SHIP THE MEDEA. 81 



cellence of their performance, appeared to realize the perfection of what we may call the art of 

 steam navigation in its then state of advancement, yet that the necessary qualifications for an 

 armed ship of any sort, particularly for distant cruizing and extended voyages, with a power- 

 ful armament and large crew, differed so essentially from those of a merchant vessel, as to 

 render it extremely dangerous to follow without variation even the most approved plan 

 of any commercial steamers, whose sole object was the conveyance of passengers and 

 cargo on coasting voyages, never at that time extending beyond four or five hundred 

 miles, and throughout the whole of which route, they generally had some port of refuge, 

 to which they might have recourse, either in extremely bad weather, or for a supply of fuel if 

 necessary. 



In carrying into effect this plan of building a few war steamers, it became important that 

 they should be so constructed as to be able to cruize, and make long passages under sail 

 alone ; it being obvious that if a war steamer is to be dependent on the power of her engines 

 for every movement, she will in all probability exhaust her resources, before arrival at her 

 scene of action. To accomplish this end, therefore, became of vital importance, and it was 

 considered unavailing for them to possess good steaming qualities, without they were in all 

 respects quite competent to act as sailing ships of war. 



Although it is unnecessary to state here all the particulars in which the construction of 

 ships of war differs from that of merchant vessels, there are some important features which so 

 much affect steamers, and have so great an influence on their character as such for velocity, 

 when competing with passenger vessels or packets, that we deem it necessary to advert to 

 them here. 



The war steamers being armed with the heaviest description of guns, one of which, weighing, 

 together with its carriage, more than six tons, is placed at each extremity of the vessel, with 

 others of somewhat less weight on the sides, it becomes necessary to afford the proper support, 

 not only when steaming in an upright position, with the centre of gravity of the displacement 

 in the plane of the keel, but perhaps engaging when under sail, with a considerable inclination, 

 and the whole weight of ordnance probably on the lee or depressed side. It is necessary, we say, 

 from these considerations, and others connected with the ponderous appurtenances of war ships, 

 among which may also be named the additional number and weight of the anchors, which are 

 always carried on the ship's side, that all the superstructure, or the whole fabric above the 

 water, should be very much stronger, and therefore heavier, than is required in any steam 

 vessel carrying passengers, or even a heavy description of cargo, which being always stowed 

 below, admits of the upper works being slight. It is also indispensable that the war vessel 

 should have a high and strong bulwark or " berthing," to afford shelter to the crew in time 

 of action : and, above all, it is necessaiy that the form of the ship should vary considerably 

 from that most calculated to insure velocity, when, as in the case of steamers, it is derived 

 from a self-contained motor, instead of being dependent on the influence ol' the wind, on sails 

 attached to the lofty and weighty masts, &c. of a sailing vessel, the oblique action of which 

 in most instances tends as much to depress the ship, as to propel her on the line of keel. Thus, 

 any vessel intended to act either as a sailing ship or steamer, must, to insure her being a 

 good sea boat, have greater stability, and more breadth of beam, than is required for one 



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