These are quoted for the whole United States at an average price of .306 c. per train-mile, but it should of course be remembered that this figure is only an average figure which will be increased or diminished very largely in individual cases. Of course the cost is greater for heavier engines and heavier trains. The proportion of the item which should be assigned to the cars, which is perhaps not more than 50%, will probably vary nearly according to the number of cars per train. The cost per engine-mile varies with the size of the engine, and will be far cheaper per ton-mile for the heavier engines than for the lighter engines. The cost of this item for engines alone seems to vary from .15 c. per engine-mile for a very light passenger-engine up to .30 c. for a very heavy freight-engine. On the other hand, it was found from some figures compiled on the A. T. & S. F. R.R., that for two engines with loads behind them of 702 and 416 tons respectively, the cost of the oil and waste per mile was .28 and .24 c, but if we reduce these figures to the cost per thousand ton-miles, the cost was .40 and .58 c. respectively. Both woolwaste and cotton-waste are used, the wool-waste costing from 50 to 100 per cent more than the cotton-waste. The wool-waste is better for the cellar of a driving-box, since it is more elastic and will therefore stand up better against the under side of the axle. Cotton-waste is even better for the tops of journal-boxes, as it lies flatter and heavier, and therefore prevents the dust from getting on to the bearings. Tallow is also used for such purposes and is far cheaper than waste. This item is so very small that we may usually neglect any variations in the amount of it, except when we are considering the economics of heavy engines vs. light engines, and then the difference is worth considering.

Other supplies for locomotives include the tools, the sand, and all miscellaneous articles, such as metal polish, torpedoes, etc. Under the head of tools it includes oilcans, lanterns, scoops, fire-bars, torches, etc. The cost of these items averages about .2 c. per train-mile, although the figure may vary 50% each way.

83. Comparative Cost Of Various Types Of Locomotives

In Table XI are given the comparative costs of the various sizes of standard-gauge locomotives, the figures having been furnished through the courtesy of the Baldwin Locomotive Works. While these figures must be considered approximate, since the actual cost of a locomotive depends somewhat on the particular kinds of attachments which are used, the table has its value in indicating to an engineer the approximate cost of the desired equipment for a new road, and also shows the comparative costs of the various types of engines. The last column is particularly instructive, since it indicates the great economy of the Mogul type, and even more so of the Consolidation type, where the maximum of tractive power, rather than high speed, is the prime consideration. The table refers exclusively to simple locomotives. As a very approximate figure it may be stated that the cost of building any of these locomotives on the compound type will be approximately $2500 more than that of the corresponding simple type.

Table XI. Comparative Cost Of Various Sizes Op Standard-Gauge Simple Locomotives. Baldwin Locomotive Works

83a. Statistics On Locomotives

The I. C. C. report for 1910 shows the number and kinds of locomotives in that year, excluding those used by switching and terminal companies.

Total Number And Kinds Of Locomotives, United States, 1910

Average Characteristics Of Locomotives, United States, 1910

About 5% (2981) of these locomotives burn oil. Two hundred of them are of the Mallet type, of which 34 are oil burning. It is very significant that in the six years since 1904, the gross number of 4-cylinder compounds has decreased from 1968 to 1511, or from 4.3% to 2.6%, and the number of 2-cylinder compounds has decreased from 932 to 862, or from 2.0% to 1.5%. The demonstrated saving in fuel in operating compound engines seems to be overbalanced by increased maintenance charges and depreciation. The common method of indicating the running gear of locomotives is by a series of three numbers of which the first is the number of pilot wheels, on both sides, the second the number of drivers, and the third the number of trailing wheels. The tender wheels are not included. If there are no pilot wheels or trailing wheels, that fact is indicated by 0. For example, a "mogul" type, having two pilot wheels, six drivers, and no trailing wheels is indicated by 2-6-0. This system is used in Table XL Of the 55,867 single expansion locomotives in use in 1910, 31.1% were of the 2-8-0 or "consolidation" type, 18.7% of the 4-6-0 or "ten-wheel" type, 16.3% of the 4-4-0 or "American" type, 12.0% of the 0-6-0 or common switching-engine type, and 9.7% of the 2-6-0 or "mogul" type. The remaining 12.1% were divided among 24 different types.