Mathematical and Physical Papers. 215 



0.5 of one per cent., while there would be a difference of less than 

 one per cent, between it and directly applied water power in New 

 England. Freight differences on raw materials would probably 

 more than counterbalance this difference, so that the cotton-mill 

 in Kansas will be on the same plane with the New England mill 

 as betwen power cost and freight, while with natural gas at 25 cents 

 per 1000 cubic feet it will be better off on power alone by 0.2 of 

 one per cent, in dividends. 



It is almost useless to make calculations for power costs from 

 crude petroleum as a fuel. The price is subject to great fluctua- 

 'tion, and if it should be adopted to any very considerable extent 

 in manufacturing plants it is extremely doubtful if the supply 

 would be adequate, in view of the great demand for the lighter 

 distillates, and in any case the price would greatly increase. Un- 

 der present conditions in Kansas it offers great advantages as a 

 substitute for coal, especially when used in the oil-engine. 



In point of economy in fuel consumption there can be no doubt 

 as to the superiority of the gas- and oil-engines over the steam-en- 

 gine. This does not mean that the latter is to be at once relegated 

 to the junk heap, however. At the present stage in the develop- 

 ment of the internal-combustion engine, its small financial ad- 

 vantage, as shown in the preceding calculations, is often offset by 

 the practical usefulness of steam in auxiliary service, to say noth- 

 ing of the advantage accruing from the familiarity of operating en- 

 gineers with the older type. 



As it has taken a century and a quarter to develop the steam-en- 

 gine since it first assumed its practical form in the hands of Watt; 

 so must more time be given to perfect this later type of prime 

 mover which first appeared in really successful operation in 1876. 

 The gas-engine is now passing through a transitional period, while 

 it is coming into prominence as a real factor in the larger business 

 interests of the world. The new form of Westinghouse engine al- 

 ready described shows the manner in which the type is progressing, 

 following instinctively the path of progress marked by the steam- 

 engine, but standing as a more economical machine. It is moving 

 far more rapidly than did the steam machine, and even now, as the 

 latest and most improved steam motor, the turbine, is being per- 

 fected and successfully established as a positive step in advance, 

 prominent European scientists and at least one of the prominent 

 engine-building companies of this country are working on the gas- 

 turbine, which we may expect to see making its appearance in the 



