[Footnote B: A car-foot mile is a unit equal to moving one foot in car length (regardless of width or height) one mile. Thus to move a car sixty feet long one mile results in sixty car-foot miles; to move the same car three miles results in 180 car-foot miles, etc.] Thus it appears that the space on passenger trains required for the mails is proportionately less than three-quarters as productive as that devoted to passengers, express, milk, excess baggage, etc., etc. As it is the general belief of railway managers, whose conclusion in this respect has rarely if ever been challenged, that the passenger train services, as a whole, do not produce revenues sufficient to meet their fair proportion of the operating costs and the necessary return upon investment, and therefore are not reasonably compensatory, it is evident that the mail service, the pay for which is more than twenty-five per cent. below the average for the other services rendered on the same trains, must bring in much less than reasonable compensation. Certainly railroad revenues as a whole could not be reduced twenty-five per cent. without destroying all return upon the property. If so, it must be true that there can be no compensation in a rate of mail pay that is twenty-five per cent. less than the rate of pay for passenger traffic which, as above shown, is relatively unprofitable. No merely statistical comparison can, however, reveal the whole story for the railways are required to furnish many incidental facilities and to perform many additional services for the Post Office Department, which render the mail service exceptionally arduous and costly. These extra services include calling for and delivering mails at a large proportion of the post offices located at railway towns; supplying rooms, with light, heat and water, in railway stations for the use of the mail clerks; placing cars, duly lighted and heated, on station tracks for advance distribution, often many hours before the departure of trains; carrying officers and agents of the Post Office Department as passengers but without compensation to the extent of more than 50,000,000 passenger miles annually (this being, of course, in addition to the railway mail clerks on duty), etc., etc. Extracts from the "Postal Laws and Regulations" defining and demanding these services are given in Appendix A. No one can examine this appendix and not be convinced that the mail service is the most exacting among all those rendered by American railways.