[1] It is proper here to say that English engineers now appreciate the merits of the American swivelling truck or bogie. In the article on Railways in the last edition of the "Encyclopædia Britannica," speaking of locomotives, the author of the article, who is an English engineer of high authority, says: "American practice, many years since, arrived at two leading types of locomotive for passenger, and for goods traffic. The passenger locomotive has eight wheels, of which four in front are framed in a bogie, and the four wheels behind are coupled drivers. This is the type to which English practice has been approximating." The italics are ours.
[2] The statistics of ten leading English and ten leading American lines, given by Dorsey, show the following results: 1. The cost per year of the rations, wages, fuel of an American locomotive is $5,590; of an English locomotive, $3,080. 2. Average yearly number of train-miles run by American locomotive, 23,928; English locomotive, 17,539. 3. Yearly earnings: American locomotive, $14,860; English locomotive, $10,940, although the English freight charges are much greater than those of the United States.
[3] The writer has obtained many of the statistics used in this article from A. M. Wellington's "Economic Theory of Railway Location," a perfect mine of valuable information upon all such matters.
[4] The amount of permanent wood and iron truss bridges, and of temporary wooden trestles on the Chicago, Milwaukee, and St. Paul is as follows:
| Truss bridges, | 700 | spans, average | 93 | feet, | 124/5 | miles. |
| Trestle " | 7,196 | " " | 77 | " | 1031/10 | " |
| —— | ——— | |||||
| Total, | 7,896 | 1159/10 | " |
The approximate total number of bridges in the United States was in 1888:
| Iron and wood truss bridges, | 61,562 | spans, | 1,086 | miles. |
| Wooden trestles, | 147,187 | 2,127 | " | |
| –——— | –—— | |||
| Total, | 208,749 | 3,213 | " |
Probably three-fourths of the truss bridges are now of iron or steel, and may be considered perfectly safe so long as the trains remain upon the rails and do not strike the side trusses. The wooden trestles are a constant source of danger from decay or burning or from derailed trains, and should be replaced by permanent structures as fast as time and money will allow.
[5] See following article on "Feats of Railroad Engineering," [page 86.]
[6] For fuller description of work in a caisson see "Feats of Railway Engineering," [page 69.]