_Great Western Railway.--Average Speed and Weight of Express
Trains._

------------------+---------------------------+----------------------
| Speed to first stopping |
| station. | Weight of train.
+-------+--------+---------+-------+---------+-----
| | | Average | | |
Train. | | | speed-- |Engine |Carriages|
| | |miles per| and |and vans,|
|Station|Distance| hour. |tender.| empty. |Total
------------------+-------+--------+---------+-------+---------+-----
| | miles | | tons. | tons. |
BROAD GAUGE TO WEST OF ENGLAND: | | | |
9.0 Paddington to |Reading| 36 | 47 | 67 | 149 | 216
Plymouth | | | | | |
11.45 do. |Swindon| 771/4 | 53 | 67 | 104 | 171
| | | | | |
NARROW GAUGE TO THE NORTH| | | | |
10.0 Paddington to|Reading| 36 | 39.2 | 60 | 190 | 250
Birkenhead | | | | | |
4.45 do. |Oxford | 631/2 | 48.8 | 60 | 129 | 189
------------------+-------+--------+---------+-------+---------+-----

[Illustration: FIG 2.--GREAT WESTERN RAILWAY.]

The narrow gauge trains are worked by two classes of engines. The first is
a single engine with inside cylinders 18 in. diameter, 24 in. stroke. The
driving wheels are 7 ft. diameter, and the leading and trailing wheels 4
ft. The frames are double, giving outside bearings to the leading and
trailing axles, and outside and inside bearings to the driving axle; this
arrangement gives a very steady running engine, and insures, as far as can
possibly be done, safety in case of the fracture of a crank axle. The
frames are 15 inches deep, of BB Staffordshire iron. The wheel base is,
leading to driving wheels, 8 ft. 6 in; driving to trailing wheels, 9 ft.;
total, 17 ft. 6 in. The boiler is of Lowmoor iron, 10 ft. 6 in. long and 4
ft. 2 in. outside diameter. The grate area is 17 square feet, and the
heating surface is, tubes, 1,1451/2 square feet; fire-box 133 square feet;
total, 1,2781/2 square feet. The boiler pressure is 140 lb. on the square
inch, and the tractive power per lb. of mean pressure in