Consider the Milwaukee's important experiment in somewhat greater detail. It has been loath to give out exact figures as to its savings in dollars and cents by its electric installation until a number of years of operation should determine these beyond a point of quibbling or of argument. Some of its economies are quite obvious however. I am not going into the remarkable system of "regenerative braking" under which in the course of a year some 60 per cent. of the current taken from the overhead trolley-wire by the road's electric locomotives is returned to that thread of copper by the seemingly simple expedient of turning the locomotive's motor into a dynamo momentarily and so utilizing the ancient force of gravity upon a descending mountain grade as to actually turn out electric current and return it to the unseen treasury through that connecting medium of a copper wire. It is enough to say that a 60 per cent. return of current is an appreciable amount. If you do not believe this, ask the next trolleyman that you meet what it would mean to his road if 60 per cent. of the coal which his power-houses have reduced to ashes could be returned to good coal again--and an infinite saving made upon brake-shoes into the bargain. These things have been told. But there has not been told publicly before this time a comparison of operating costs between the Missoula division--half of the Harlowton-Avery electrified section of the Milwaukee--and an adjacent mountain division which in 1918 and 1919 was not electrified, and which moreover is not subjected to the extremely hard winters of the Missoula range. The cost of locomotive repairs for 1918 and 1919 on this steam division was two and one-third times as great as upon the electric, owing in no small degree to the fact that the electric locomotive handles heavier trains and at higher speed than the steam, yet, notwithstanding this increased capacity, has a much lower maintenance cost per mile run. The cost of train crews was nearly two and one-half times greater on the steam division than upon the electric--this also because of the greater train tonnage and speed under electric operation. The expense for enginemen for similar reasons was 55 to 60 per cent. greater on the steam operation. It is easy enough to talk in generalities, much harder sometimes to come to the brass tacks of a situation. It is a sort of brass tack, isn't it, when on this steam division of the Milwaukee, the engine-house expense was two and one-half times greater than upon the electric--and for reasons that we have already seen? We do not need the exact dollars and cents of saving, when these comparisons are placed before us.