The engine is supplied with a return flue, straw, wood and coal burning
boiler. The shell of the main flue is cylindrical in shape, but tapers
toward the front end. By this arrangement the return flues can be set
lower at the front end, which it is claimed has some advantage in
protecting front end of flues when ascending steep hills.
The steam used is superheated by being conducted through a pipe which
extends from the top of the dome on the inside of boiler through the
front head and smoke stack to the steam chest.
The engine is of the Side Crank, Side Gear style, the frame of which is
the girder pattern with bored guides, and has an overhanging cylinder
attached to one end, and contains the pillow block bearing at the other.
It is fitted with the Woolf Valve Gear for reversing, Friction Clutch,
Cross-head Pump, Injector, Syphon for filling water tank on front end,
and a large Foot Board with Tool Boxes attached. The wheels are of
steel, and the traction or drive wheels are furnished with malleable
mud cleats extending diagonally across the entire width of tire.
The boiler is safe with proper care, economical in fuel, and the
engine moves over the road rapidly. Although simple in its general
construction, it has all the appliances and fittings necessary on a
traction engine.
[Illustration: Minneapolis Traction Engine.]