MEMOIR OF HER MAJESTY'S STEAM SHIP THE MEDEA. 85 



Expence in money, (English prices,) of coals and engine stores, (say tallow, &c.) . s. d. 



24 hours' steaming 16 12 



,, per mile, about . 1 1\ 



,, ,, (Malta prices,) 24 hours . . 24 10 



,, per mile, about . 2 4| 



Rate of steaming, with 320 tons of coal and war equipment on board, in a calm, 8J- knots per hour. 

 ,, ,, when lightened by the expenditure of one-third the fuel 9|- ,, ,, 



., ,. of two-thirds 10 ,, ,, 



She will therefore go at 8' knots an hour about 1190 

 ,, ,, at 9 knots an hour ,, 1258 



at 10 knots an hour 1360 



Thus accomplishing the distance of 3808 knots, or geographical miles. 



Each rate being attained by a gradual progression, as the ship lightens from the expenditure 

 of coals, and as the latter part of the distance may be at a speed even above ten knots ; some 

 addition should be made to the gross amount above stated : it must however be observed, 

 that the experiments from which the foregoing data are taken, were all made in calm 

 weather; but, as the consumption of fuel is by a judicious arrangement of the dampers, and 

 by slackening the fires, considerably lessened as the speed is diminished from the violence of 

 the wind or sea, we may safely state, that the Medea is competent to undertake any voyage 

 of at least 3000 miles, except a westerly passage across the North Atlantic in the winter 

 season ; at which period of the year the ocean between England and America is swept with 

 scarce an intermission by violent westerly gales, creating waves which, even supposing the 

 temporary cessation of the wind, must oppose an effectual barrier to the favourable operations 

 of any steamer. We by no means presume to state that the voyage cannot be made, or these 

 difficulties safely overcome, by a powerful vessel with a large supply of fuel ; but her progress 

 at times must be very slow ; and though, no doubt, in such a case she might cross the 

 Atlantic in much less time than a sailing ship under similar circumstances, it would be at a 

 speed far below the usual rate of steaming voyages. 



It is proper to state, with reference to the coal carried by the Medea, that the weight of 

 the armament and war materiel is quite equal to 50 tons, and consequently, that if disarmed, 

 she could carry fuel without being further immersed in the water, or her progress thereby 

 impeded, sufficient for a voyage the extent of which may be at least 500 miles more than the 

 distance before stated : she might therefore be sent to the West Indies with despatches, or 

 even troops, at a few hours' notice, almost with a certainty of reaching Barbadoes, or any 

 other of the windward islands, in nineteen, or at most twenty, days, under the average 

 circumstances of weather usually experienced in that voyage. 



Speed of the Medea with the wheels detached from the engine, and revolving by the reaction 



of the water as the ship is impelled by the influence of the wind on her sails. 

 Blowing strong, smooth water, close hauled " within " 6 points . . 8 knots 

 Blowing strong wind on the quarter ....... 



1 Including cost of conveyance to, and stoppage at, Malta. 



