TABLE

SHOWING THE STEAM PRESSURE IN POUNDS PER GAUGE; THE ABSOLUTE PRESSURE IN POUNDS AND INCHES OF MERCURY; THE TEMPERATURE; THE TOTAL HEAT IN STEAM PER POUND; THE LATENT HEAT PER POUND; THE HEAT OF THE WATER; THE RELATIVE VOLUME AND WEIGHT OF STEAM PER CUBIC FOOT, FOR VARIOUS PRESSURES.

The Brown Automatic Cut-Off Steam-Engine.

The cuts on pages 89, 90, represent the Brown Automatic Cut-off High-pressure Engine.-The housing, which, as will be observed, is of the girder-frame pattern, somewhat resembles the Corliss, though the engine is different in every other respect. The cylinder, which contains the steam- and exhaust-ports, is encased in an ornamental cast-iron jacket, and rests on a square, tapering column which extends nearly the full length. By a judicious distribution of the materials, every part possesses sufficient rigidity, without extra weight of metal. In its design, the evils induced by expansion, and the liability to get out of line, have been scientifically considered and practically obviated. A spur-gear on the main shaft gives motion to a shaft parallel with and below the axis of the cylinder. From this shaft the motions of the valves are derived.

There are four valves, one steam and one exhaust at each end of the cylinder, which are independent, and though slide-valves, as they have but one function to perform for each revolution, i. e., admitting or exhausting the steam, they are necessarily of a different construction from the ordinary slide-valve. The exhaustvalves are horizontal, and travel at right angles with the cylinder; the motion being derived from cams on the longitudinal shaft, which is positive in both directions. The shape of the camways is such that the motions of the valves in opening and closing are very quick, and allow of their remaining stationary during nearly the whole stroke of the piston, thus insuring a perfectly free exhaust, and preventing any possibility of back pressure.

The steam-valves, which are vertical, are of the gridiron pattern, and require very little movement to give a full port opening. They are operated by eccentrics on the cam-shaft, in connection with the following device for regulating the point of cut-off. A vibrating lifter, having the fixed centre at its outer end, is connected, at about the middle of its length, with the eccentric-rod; while the inner end engages a spring-catch or projection on the

The Brown Automatic Cut-Off Steam-Engine.

The cuts on pages 89, 90, represent the Brown Automatic Cut-off High-pressure Engine.-The housing, which, as will be observed, is of the girder-frame pattern, somewhat resembles the Corliss, though the engine is different in every other respect. The cylinder, which contains the steam- and exhaust-ports, is encased in an ornamental cast-iron jacket, and rests on a square, tapering column which extends nearly the full length. By a judicious distribution of the materials, every part possesses sufficient rigidity, without extra weight of metal. In its design, the evils induced by expansion, and the liability to get out of line, have been scientifically considered and practically obviated. A spur-gear on the main shaft gives motion to a shaft parallel with and below the axis of the cylinder. From this shaft the motions of the valves are derived.

There are four valves, one steam and one exhaust at each end of the cylinder, which are independent, and though slide-valves, as they have but one function to perform for each revolution, i. e., admitting or exhausting the steam, they are necessarily of a different construction from the ordinary slide-valve. The exhaustvalves are horizontal, and travel at right angles with the cylinder; the motion being derived from cams on the longitudinal shaft, which is positive in both directions. The shape of the camways is such that the motions of the valves in opening and closing are very quick, and allow of their remaining stationary during nearly the whole stroke of the piston, thus insuring a perfectly free exhaust, and preventing any possibility of back pressure.

The steam-valves, which are vertical, are of the gridiron pattern, and require very little movement to give a full port opening. They are operated by eccentrics on the cam-shaft, in connection with the following device for regulating the point of cut-off. A vibrating lifter, having the fixed centre at its outer end, is connected, at about the middle of its length, with the eccentric-rod; while the inner end engages a spring-catch or projection on the