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PEOFESSOR 0. REYE'OLDS AND MR. W. H, MOORBT 
and a little behind and lower, is another bowed pipe leading from the top of the brake, with a gap in it; 
this is the air passage leading through the ranes to the centres of the vortex chambers, to secure atmo¬ 
spheric pressure there. The suspended and riding loads on the lever, the dash-pot, the front stop on 
which the lever rests (not being at work), are also seen. The hand w^heel for adjusting the height of 
the lever when at work, the linkage connecting the automatic inlet and outlet-cocks with each other 
and with the front stop, together with the outlet-cock, the receptacle for waste, and the drip-can for the 
water escaping from the front bush, can be traced, though they are obscure in this plate. 
Up high on the photograph is seen a shaft with two lai’ge pulleys ; these are for connecting the 
separate engine-shafts by belts and ropes (seen), and have no place in the trials. But the bright shaft 
immediately below, seen as driven by a rope pulley from behind the wall of the engine-room, is the line 
shaft driven by the separate engine, always running, which afforded most important facilities for the 
research. 
PLATE 4. 
From a photograph, 1896. Also shows a front view of the engine-room, but, taken more to the right; 
it includes only the low-pressure engine. It shows a general front view of the appliances in the con¬ 
dition in which they were during the final experiments, as well as some of the standing appliances not 
included in Plate 3. 
Low down, immediately on the right, is the front of the weighing-machine, with the tank resting on 
it; and immediately behind this, against the wall, are seen the mercury balances for the pressures of 
water in the mains; also the town’s main to the service tank (out of sight on the right), in front of 
which is the 3-inch quadruple turbine which drives the (1-^-inch) quintuple centrifugal pump (out of 
view, behind the tank) supplying the brake through the ice-cooler (§ 20). On the left of the tank, 
and passing through its cover, is the water-switch ; and over this is the nozzle of a vertical pipe, straight 
almost to the roof, then horizontal, with an open vertical branch, to form an air-gap, then down again 
into the lower of the two horizontal pipes; this is the stand-pipe on the outlet from the condenser, for 
securing pressure in the final thermometer chamber (§ 22). The upper of the two horizontal pipes is 
the water-jacketed out-flow pipe or “ condenser,” w'hich passes to the end of the room, and returns as the 
lower horizontal pipe to the stand-p^pe. Immediately on the left of the plate, standing on the floor, is 
the frame for the hand-brake (§ 30). Besides the appliances mentioned, as seen, in this plate, nearly all 
the appliances are seen in front view ; but many are better seen in the following plates, though this plate 
affords the best view of the general arrangement, and the best idea of the circumstances under which 
the observations were made. The passage between the brake and the 3-inch pipe supplying condensing 
water to the engine afforded the only post of observation for the counter, thermometers, speed-gauge, 
and pressure-gauges. The centrifugal speed-gauge, with its scale, is seen rising vertically from behind 
the small pressure-gauge on the brake. 
PLATE 5. 
This is a nearer and simplified front view of the more special appliances shown in Plate 4. Proceeding 
from the right is the switch and outlet nozzle from the condenser, with the wmter flowing into the tank 
over the thermometer. From the switch may be traced the linkage forming the automatic connection 
of the sw'itch with the counter, immediately in front of the covered bush of the brake. Supported by 
the original supply pipe to the brake (the hand cock being shut) is seen the new inlet pipe from the ice- 
cooler, behind the brake. The pipe, rising on the right from behind the brake, passes a branch to the 
by-channels leading to the bushes (not seen) and a branch to the large pressure-gauge, then to the 
regulator ; thence the water flows upwards past the bulb of the inlet thermometer, some of it passing 
up through the glass thermometer chamber, and so to wuste through the small pipe at the top, but the 
main stream passing through the covered horizontal branch, and down the flexible iiidiarubber pipe 
