Mr. Stirling conducts his traffic at a higher rate of speed, and
certainly with equal punctuality, with his magnificent single 8 ft.
engines, as Mr. Webb on the North-Western with coupled engines, and the
economy of fuel of the former class over the latter is very remarkable;
this is, no doubt, owing, as has been previously pointed out, to their
ample cylinder power, which permits of the steam being worked at a high
rate of expansion. There is no doubt that if single engines can take the
load they will do so more freely and at a less cost than coupled engines,
burning on the average 2 lb. of coal per mile less with similar trains.
With, regard to loads, it is a question whether any express train should
be made up with more than twenty-five coaches. The Great Northern engine
will take twenty-six and keep time, and the Brighton single engine has
taken the five P.M. express from London Bridge to Brighton, consisting of
twenty-two coaches, at a speed of forty-five miles per hour. Of course
where heavy gradients have to be surmounted, such as those on the Midland
route to Scotland, coupled engines are a necessity. Single engines are
said to slip more than coupled; thus an 8 ft.
Pages:
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107