680 
Report 011 the Trials of Portable 
arrangement is made whereby the plummer blocks may slide horizontally on a 
planed bed to permit of expansion. The valve gear consists of a single 
slide-valve, driven by an eccentric of variable travel, controlled by a Hartnell- 
Turner governor on the crank shaft. [This governor, now well known, was 
fully described and figured in the Report of the Cardiff trials, and needs, 
therefore, no further notice here.] The pump lies at an angle with the crank 
shaft, and the feed is heated by a neat bye-pass arrangement. Such feed 
water as does not go into the boiler returns to the tub, meeting, on its way, 
with a portion of the exhaust steam, the steam and water mingling in a 
conical annular chamber which, forming the termination of the exhaust branch- 
pipe, acts the part of an aspirator, and carries the surplus water, together 
with the water of condensation from the exhaust, back to the tub. This is a 
pretty arrangement first introduced, it is believed, by Messrs. Garrett of 
Leiston. There are two safety valves placed over the cylinder jacket and 
controlled by spring-balances. The chimney is raised and lowered by means 
of "Coultas' patent chimney-raiser," consisting of a small barrel, with winch 
and chain. 
This engine was first declared to run at 16 brake-horse 
powers, and 130 revolutions ; but, the preliminary trial having 
demonstrated that the Hartnell-Turner governor could not keep 
the number of revolutions down to the declared limit, the 
revolutions were increased to 145, the brake load remaining 
unaltered. Similarly, the declared steam pressure was 85 lbs., 
but the engine over-ran so much at this pressure that, during 
the greater part of the trial, the pressure was kept down to 
70 lbs. With 70 lbs. of steam, the engine ran fairly steadily 
at about 145 revolutions, but, with any variation in the load, 
there would have been, practically, no control of the speed. 
The engine ran for 4 hrs. 1 min. actual, and 4 hrs. 2 mins. 
mechanical time, with a coal supply of 351 lbs., equal to a 
consumption of 5*11 lbs. of coal per horse-power per hour. 
Simple Engine, by Messrs. Jeffery and Blachstone (No. 147). — 
This was the first engine to be tried on the 7th of July, and, 
belonging properly to quite another class than that of ordinary 
Agricultural Portable Engines, its performance, which was in no 
way remarkable, may be dismissed with a brief notice. The 
engine, nominally of 3-horse power, is of the vertical type, 
arranged for travelling. 
A multitubular boiler is mounted on two travelling wheels and fitted witli| 
a pair of singk-horse shafts, wliosc position, relatively to the upright boiler,'i 
is such, that the latter, when on the road, assumes an inclined position, the 
weight preponderating on the shaft side of the axle. 
When at work, the shafts are removed, and the boiler, now in a vortical 
position, is steadied by three stay-legs, two forward and one aft, wliich 
certainly kept the machine very steady while under trial. The cylinder if 
placed below the crank-shaft and is not jacketed, while the valve gear consists 
of a single slide valve. A small governor, running slower than the engine, 
operates a throttle valve for regulating the speed, and the pump draws auc 
delivers cold water. . 
