Multiplying these differences into thousands of miles of line shows the great economy resulting.
[35] Cf. pp. [259] and [422], infra.
[36] The provision of plant and equipment to carry the "peak of the load" is often a serious handicap.
[37] For an instance of detailed analysis of cost, the general investigation of soft coal rates to the lakes in 1912 is highly suggestive. Two-thirds of revenue went for operation and maintenance, one-third for return upon plant. This was the first attempt to justify an advance in rates for a large volume of traffic on the ground that it did not contribute its proportionate share of earnings. 22 I.C.C. Rep., 604.
[38] From Railroad Operating Costs; by Suffern & Co., New York, 1911.
[39] Lorenz in Quarterly Journal of Economics, XXI, pp. 283-292, is suggestive.
[40] Change of accounting methods vitiates further comparisons of operating costs after 1907.
[41] From Railroad Operating Costs, by Suffern & Co., New York, 1911.
[42] Cf. Yale Review, 1910, pp. 268—288; with reference to the rate advances of that year.
[43] Cf. the Free Cartage case, 167 U.S., 633.