It is in the increased capacity of locomotives and cars rather than in their numbers that the seeker after truth will find the explanation of how American railways have been able to handle freight traffic that has increased in volume over 80% in ten years where numerically the increase of equipment has been less than 60%. During that period the average capacity of the freight car has increased from 27 to nearly 35 tons, accounting for an aggregate increase of 109.6%.
Between 1899 and 1909 the population of the United States increased from 74,318,000 to 88,806,000, or 19.5%. (On April 1, 1910, the treasury estimate was an even 90,000,000.) In the same ten years the number of passenger cars increased over 36%, accompanied by a steady advance in their size, strength and conveniences.
Between 1902 and 1907 the Official Statistics furnish the following information showing the gradual transformation taking place in the number and capacity of freight cars:
| Number and Capacity of Different Sizes of Freight Cars, 1902-1907. | |||||
| Class | Capacity Pounds | 1902 | 1907 | Increase or Decrease Per Cent | |
| I | 10,000 | 5,122 | 4,277 | Dec. | 16.5 |
| II | 20,000 | 15,615 | 7,244 | " | 53.5 |
| III | 30,000 | 46,353 | 10,132 | " | 78.1 |
| IV | 40,000 | 327,342 | 204,583 | " | 37.5 |
| V | 50,000 | 246,684 | 178,827 | " | 27.5 |
| VI | 60,000 | 634,626 | 802,187 | Inc. | 26.4 |
| VII | 70,000 | 22,493 | 34,652 | " | 53.6 |
| VIII | 80,000 | 158,179 | 452,070 | " | 185.9 |
| IX | 90,000 | 310 | 5,054 | " | 1,527.1 |
| X | 100,000 | 48,834 | 285,241 | " | 484.3 |
| XI | 110,000 | 389 | 1,476 | " | 279.4 |
| XII | 120,000 | 43 | 60 | " | 39.5 |
| All over | 120,000 | 2 | 214 | — | |
The line of cleavage between former and modern railway methods of handling freight is clearly shown in the above table to lie between cars of 25 and 30 ton capacity. The former and all of less capacity are on the decline, whereas the latter and all of greater capacity are on the increase. Numerically the 30-ton cars still exceed those of 40 and 50 tons, but already they are exceeded by the combined capacity of the latter.
The Surplus of Freight Cars.
For two years (28 months as this is written) the reports of the Committee on Car Efficiency of the American Railway Association show that the supply of freight cars has been in excess of the demand. In other words, the railways during that period were paying interest on a considerable percentage of unremunerative equipment, besides the cost of its maintenance. The rise and fall of this surplus of freight cars is set forth below:
| Freight Car Shortages and Surplus by Months from January, 1907, to April, 1910. | ||||
| Month | 1907 | 1908 | 1909 | 1910 |
| Shortage | Surplus | Surplus | Surplus | |
| January | 110,000 | 342,580 | 333,019 | 52,309 |
| February | 150,000 | 322,513 | 301,571 | 45,513 |
| March | No data | 297,042 | 291,418 | 45,672 |
| April | 100,000 | 413,605 | 282,328 | 84,887 |
| May | 60,000 | 404,534 | 273,890 | |
| June | 40,000 | 349,994 | 262,944 | |
| July(a) | 20,000 | 308,680 | 243,354 | |
| August(a) | 15,000 | 253,003 | 159,424 | |
| September | 60,000 | 133,792 | 78,798 | |
| October | 90,757 | 110,912 | 35,977 | |
| November | 57,003 | 132,829 | 39,528 | |
| December (surplus) | 209,310 | 222,077 | 58,354 | |
| (a) In July and August, 1907, there was a net surplus. | ||||