250

MODERN STEAM PRACTICE.

requires attention to keep the water in the cistern at the properlevel, and in many situations the water would require to be raisedby a separate pump, or the cistern placed low enough to admit ofthe water running in from an adjoining pond.

We give a Plate of a Winding Engine of approved construction,erected in 1881 for a pit belonging to the Benhar Coal Company,at Niddrie near Edinburgh .

BLOWING ENGINES.

OVERHEAD-BEAM BLOWING ENGINE.

We will now consider that form of engine used for blowing air tothe furnaces for melting iron ores, technically termed the “ blowing

Fig. 151.—Blowing Engine. Side Elevation.

engine.” This engine delivers the air into a receiver, the pressurevarying from 2 to 4 lbs. per square inch, or a mean of say 3^ lbs.,that being the pressure on the large piston of the blowing cylinder,