STATIONARY ENGINES.

271

placed at the bottom of the cylinder, with a connecting pipe fitted withan expansion joint, forming the passage to the top of the cylinder.A separate slide valve is also fitted for starting the engine, which is

Fig. 181.—Blowing Engine at the Dowlais Iron Works. End Elevation.

worked by hand; but the main slide valve has the ordinary eccentricmotion, with weigh shaft side rods and crosshead overhead, thevalve rod being guided at the top by a stud placed on the passagebetween the top and bottom of the cylinder. The valve rod passes