RECIPROCATING AND TURBINE ENGINES ON STEAMSHIPS. IQI 
With the reciprocating engine closing its work with a terminal pressure 
of 30 pounds absolute, a simple compound engine would give satisfactory 
results. Where the total power was to be above 8,000, I would make the 
reciprocating engine with two high and two low pressure cylinders, the high 
pressure cranks being 180 degrees apart and the low pressure cranks 180 
degrees apart, each pair being 90 degrees apart, this would produce a well- 
balanced engine. Both pairs of cylinders would have piston valves. ‘The 
valves for each pair being arranged so that one would take steam on the 
outside of the valve and the other on the inside. This would enable the 
valves for each set of cylinders to be operated by one valve gear, making an 
exceedingly simple marine engine. By a proper arrangement of exhaust 
from the low pressure cylinders, only one change valve would be necessary. 
This would be operated by a direct steam cylinder, controlled by a hydraulic 
cylinder and piston so that the movement might be as slow as required. No 
steam jackets would be needed on the cylinders. ‘The exhaust pipes, how- 
ever, from the low pressure cylinders to the turbines might be jacketed with 
advantage. 
In such an arrangement there need be no objection to operating the 
air pumps, of which there would be two, through levers worked from the 
crossheads of the low pressure cylinders. These pumps would be placed 
so that the foot valves would be as low down as possible, the channel way 
being in line with the lower face of the bed plate so as to be below the lowest 
part of the turbine casings, it being important to have them thoroughly 
drained. ‘The dry air pumps should be operated in the same manner as the 
wet air pumps, being placed above the operating levers in a direct line with 
the wet pumps. The writer, however, would prefer to have the air pumps 
independent as shown on the sketch arrangement illustrating this paper, 
which would simplify the main engine and enable the turbines to be run 
without the reciprocating engine being in use. The feed pumps would be 
operated independently and thus remove another source of trouble from the 
main engine. In nearly all cases there would be room to install the main 
condensers on the outboard side of the turbines, so placed as to have the 
exhaust passage in the middle of the length of the condenser. ‘The channel 
ways or connections to the wet air pumps would pass through the lower part 
of the turbine casings and connect direct to the lower chambers of the pumps. 
As the turbines would not be as long fore and aft as the reciprocating engine, 
there would be plenty of room for all engine room auxiliaries. 
An outline of how such an arrangement would be installed for say 20,000 
horse-power will accompany this paper. “[hedimensions of the various parts 
have not been worked out to meet any specific conditions, or to any refine- 
mentof accuracy, but are nearenoughtoshow how suchan arrangement when 
perfected would look in place, the ship having a moulded breadth of 66 feet. 
