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 = 140 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 XLIII., XLIV., XLV., and XLVI. 
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 ; 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 Il-| 
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