LOCOMOTIVE ENGINES.

727

EXPRESS ENGINE FOR TUE PENNYSYLVANIA RAILROAD.

The following description of an express locomotive for the Penn-sylvania Railroad is given by the Engmeer, Feb. 10, 1882, as anexcellent example of American practice. The boiler is of the wagon-top form, and is of steel; the grate is large, for burning anthracitecoal, and therefore water tubes are used instead of fire bars.

Weight full :—On drivers,On trailers,On bogie,

Boiler: —

Eimensions.

Diameter,

4 ft. 2 in.

Length of grate, io ft.;

Width of grate,

3 ft- sH in -

Mean height of fire-box crown

above grate,

3 ft. in.

Thickness of boiler plates,

H in -

,, internal fire box,

% in-

,, tube plates,

Y in.

No. of wrought-iron tubes, 201

; Inside diameter of tubes,

1% ' n .

Length of tubes,

10 ft. 10% in.

Grate surface, ...

35 sq. ft.

Total heating surface, ...Engine :—

. ... 1205 sq. ft.

Diameter of driving wheels, ..

6 ft. 6 in.

„ bogie

2 ft. 9 in.

Wheel base of coupled wheels,

7 ft. 9 in.

Total wheel base,

22 ft. "jY in-

Diameter of axle boxes, 8 in. ;

Length of axle boxes,

lc>Y in.

Diameter of cylinders,

1 ft. 6 in.

Stroke, ...

2 ft.

Centre to centre of cylinder, ..

6 ft. 5 in.

Lap of valves, ...

\Y in.

Width of ports, 1 ft. 4^ in.;

Length of ports,

lY. in.

Length of exhaust ports

3 % in.

15 tons.

14 tons 3 cwt.12 tons 4 cwt.

In all, ... ... ... 41 tons 7 cwt.

The tractive force is ioo lbs. per lb. of cylinder pressure.

HAULAGE POWER OF LOCOMOTIVES.

The following tabulated Statement of the relative haulage powerof locomotives is given by the Raih'oad Gazette. It is the result ofexperiments by an American raihvay Commission, and includes threetypes of engine, viz. A. American locomotive with four drivir.g wheelsand 12,000 lbs. on each wheel, total weight of engine 36 tons. B. Ten-wheeled locomotive with six driving wheels and 12,000 lbs. on eachwheel, total weight of engine about 42 tons. C. Eight driving wheelsand 12,000 lbs. on each wheel, total weight of engine about 54 tons.