line of the cylinder, to allow the rods coupling the two pistons to travel in a direct line under the crank shaft, one connecting

rod serving the purpose of the two cylinders. The cycle of operations is the same as that shown in fig. 2 at B, and fig. 4

E

FIG. 39.-100 B.H.P. FIELDING ENGINE

that is, an impulse is obtained at every revolution when working at full power.

The compressor, which was constructed by Messrs. Johnson & Co., Stratford, London, is a two-stage one, compressing the air up to 40 lbs. per square inch above the atmosphere.

FIG. 42.-1 H.P. NOM. FIELDING VERTICAL ENGINE

The engine is fitted with a Fielding high-pressure starter applied to one cylinder only. The makers state that a highly satisfactory test has been made with this plant, using producer gas, although the results were not sufficiently accurate for publication.

The vertical engine shown in fig. 42 is a departure in design from those made by other firms, the valve arrangement being very neat and compact. These points, together with automatic tube ignition and an inertia governor, give a well-designed engine.

T. B. Barker & Co., Birmingham

Messrs. Barker & Co. claim an experience in gas engine manufacture extending over a long series of years, and ranging from an atmospheric engine to the present 'Otto' type, for some time paying considerable attention to the three-cycle engine; and tests conducted by independent authorities proved that even with this type very low gas consumptions were obtained.

Fig. 43 shows their 9 H.P. NOM. size, the cylinder of which is fitted into the bed and held in its place by bolts passing through the water jacket. The valve gear is exceedingly simple, and the governor of the inertia type.

Their 16 H.P. NOM. engine, shown at fig. 44, has a cylinder 12 inches diameter and a stroke of 20 inches, and which gave most satisfactory results in an independent test, particulars of which will be found on pp. 240 to 248.

The cylinder and bed are in one casting, with a separate

base, the back cover, containing the gas, air, and exhaust valves, is water-jacketed, and is bolted to the end of the cylinder. The

practice of this firm is to fit engines of all sizes with bent cranks, automatic tube ignition, and to arrange the gear wheels which drive the side shaft between the bearing and the crank so that the flywheel or pulley may be brought close up to the bearing. The centrifugal governor fitted to this size can be

FIG. 43.9 H.P. NOM. FORWARD' ENGINE