e London, Tilbury, and Southend and
South-Western railways; the saddle tank bogie engines, working the broad
gauge trains on the Great Western Railway, west of Newton; and the
familiar class working the Metropolitan and North London traffic. But the
same principle is adopted in nearly all--a flexible wheel base to enable
them to traverse sharp curves, small driving wheels coupled for adhesion,
and wing or saddle tanks to take the water. One notable exception is,
however, the little six wheel all-coupled engines weighing only 24 tons,
which work the South London traffic, burning 241/4 lb. of coal per mile,
with an average load of eleven coaches.

Goods engines on all lines do not vary much. As a rule they are six wheel
all-coupled engines, with generally 5 ft. wheels, and cylinders varying
between 17 in. and 18 in. diameter and 24 in. to 26 in. stroke; the grate
area is about 17 square feet, and the total heating surface from 1,000 to
1,200 sq. ft.; the average weight in full working order varies from 30 to
38 tons. One noteworthy exception occurs, however, on the Great Eastern
Railway, where a type of goods engine with a pony truck in front has been
introduced. The cylinders are outside 19 in. diameter and 26 in. stroke,
there are six coupled wheels 4 ft. 10 in. diameter, and the pony truck
wheels are 2 ft. 10 in. diameter; the total wheel wheel base is 23 ft. 2
in., but there are no flanges on the driving wheels. The boiler is 11 ft.
5 in. long and 4 ft. 5 in. diameter, the boiler pressure is 140 lb., and
the tractive force per lb. of mean cylinder pressure 162 lb.; the grate
area is 18.3 square feet, and the heating surface is in the tubes, 1,334
square feet; fire-box, 122 square feet; total, 1,456 square feet.

The weight in working order is on the pony truck, 8 tons 10 cwt.; leading
coupled, 12 tons 8 cwt.; driving coupled, 13 tons 5 cwt.; trailing
coupled, 12 tons 15 cwt.; total, 47 tons.

The tender weighs 28 tons in full working order. These engines take 40
loaded coal trucks or sixty empty ones, and burn 52 lb. of coal per train
mile, the worst gradient being 1 in 176. A notice of goods engines would
not be complete without alluding to a steep gradient locomotive, and a
good example is the engine which works the Redheugh Bank on the
North-Eastern Railway. This incline is 1,040 yards long, and rises for 570
yards 1 in 33, then for 260 yards 1 in 21.7, for 200 yards 1 in 25, and
finally for 110 yards 1 in 27. The