346 REPORT—1863. 
discharge it through the scuppers. This arrangement, which was introduced 
by Mr. Laird, has been found very convenient, in freemg the decks quickly 
from water. These iron gunwale plates are 5 ft. wide by ? in. thick amidships, 
tapering gradually to about 2 ft. 6in. by in. at the ends, with a system of 
diagonal tie plating from side to side, securely bolted or riveted to the deck 
beams. Between the paddle-boxes, an upper deck, about 50 ft. in length, 
has been placed. It is laid on iron beams well secured, and being provided 
also with diagonal tie plates, it further adds to the strength amidships; 
though the primary object was for the more rapid embarkation and landing 
of passengers and luggage at times of low water, both at Holyhead and at 
Kingstown. It also forms an agreeable promenade for the passengers in 
moderate weather. The wheel and the binnacle are placed on this upper deck, 
so as to allow of the commander and the officers being near to the men engaged 
in steering. All difficulty is thus avoided in passing the word, a distance of 
nearly 200 ft., as would have been necessary, in the ordinary way. ‘The 
entire of the main deck, from the foremost funnel to the bows, is covered over 
by a hurricane deck formed with angle-iron beams, 5 in. by 22 in., extending 
from the rail at each side, and boarded over with planks 13 in. thick, leaving 
when at sea but one small opening round the foremast. This construction 
has been found of great advantage in throwing off the seas, which, pre- 
viously to the vessels being thus protected, occasionally in heavy weather 
caused damage to the skylights and the upper works. The weight of so 
large a piece of work, about 140 ft. in length, is considerable, and increases 
the immersion of the vessel forward; but this has been amply compensated 
for by the security afforded when pressing at a high rate of speed in 
tempestuous weather. There has not been the slightest damage to any of 
the vessels, during the last two years, since they were completely provided 
with this excellent protection. The plan was copied from a small vessel, the 
‘Menai,’ fitted out in Liverpool for the River Plate in 1854. 
The engines for all the vessels are on the oscillating principle. In the two 
pairs made by Messrs. Ravenhill, Salkeld, and Co., for the ‘ Leinster’ and 
the ‘Connaught,’ the cylinders are 98 in. diameter, with a length of stroke of 
6 ft. 6in.; the air-pumps are 54 in. diameter, with a stroke of 2 ft. 6in. The 
eight boilers are multitubular, four being at each end of the engine-room 
space, arranged in pairs, with one funnel to each pair. There are five fire- 
grates in each boiler, 3 ft. lin. wide, with bars 5 ft. 6in. long. The boilers 
being placed lengthways in the vessel, the firing-space, which is 11 ft. wide, 
is in the centre. The entire extent of the grate surface in the eight boilers 
is 677 square feet; and the heating surface measures 19,700 square feet. 
The bunkers are small, being made to contain only one day’s coal, as the 
vessels can be supplied either at Holyhead or at Kingstown, during the 
interval between their arrival and departure. The space occupied in the 
length of the vessel by the engines and boilers is 108 ft., and this has been 
subdivided, by iron water-tight bulkheads, into three compartments, an 
arrangement suggested by Mr. Laird, and which has been found most bene- 
ficial in giving strength in a part of the vessel which might otherwise have 
been weak, and unequal to the severe strain of the powerful machinery 
working in the heavy seaway of the Irish Channel. The wheels, which are 
constructed on the feathering principle, with fourteen floats each, are 31 ft. 
in diameter at the outside of the floats, or 27 ft. to the centre of axis; and 
each float is 12 ft. long by 4ft. 4in. broad. On the trial trips, the engines 
worked at the rate of 25 revolutions per minute, under a steam pressure of 
25 Ibs. per square inch. The mean of the runs of the ‘Leinster,’ at the 
