EXPLANATION OF THE PLATES. 369 



horses' power. But the speed of the piston is taken at 185 feet, large allowances are 

 made which the present improved state of workmanship perhaps renders unnecessary, 

 and the engines are estimated at 2 x 70 = 1 40 horses' power. Probably for a sea- 

 going vessel, where the engines often cannot work at their proper speed, we are 

 right in so doing. 



PLATES XLTIL, XLIV., XLV., AND XL VI. 



The drawings in these plates shew an elevation, plan, and two sections of the 

 engine room of those armed Russian steam ships Jason and Colchis, lately built by 

 Messrs. Fletcher and Fearnall, of Limehouse, and fitted with engines by the Butterly 

 Company for the Imperial Government, under the direction of Mr. Glynn. It has 

 been thought unnecessary to give a drawing of the boilers, as they are similar to 

 those made for our own government, and differ only in dimensions. The difference 

 of dimensions is shewn in the general drawing, the internal construction being the 

 same as shewn in the boilers of her Majesty's steamers Hermes, Firefly, and Spitfire, 

 Plate XLII. The Jason and the Colchis are, it may be said, sister ships, but the 

 Colchis being the last built, some slight alterations were made by the constructor, Mr. 

 Fearnall, and the Colchis was his last work as it was his best. This celebrated 

 shipwright died on the 23d of October, 1837 5 and for the construction of steam ships 

 he had no superior. The vessels being expressly designed for the Black Sea, and 

 this being a shallow sea, carried ten days' fuel, and with all their stores and equip- 

 ments drew only 9 feet 6 inches water; yet with only 2 x 60 horse power engines 

 they were propelled through the water at the rate of 10 nautical miles (or about 11-g 

 statute miles) per hour. They each carry one long heavy gun (a 32 pounder) in 

 midships on the quarter deck, besides two bow guns for chasing a flying enemy; also 

 32 pounders, and smaller, guns for signals and salutes. They lie very low on the 

 water, and as war steamers, are formidable antagonists, whilst their capabilities as 

 sea boats have been put to severe trials in the Bay of Biscay in heavy gales of wind. 



3 A 



