Size-500-hp (rated) plant, full load. Two 250-hp producers-10-hour day. Three 250-hp producers (one spare)—24-hour day. Engine-room costs-Same in both cases. Base cost of plants-Dollars per horse-power = anthracite, $14; bituminous, $22. Erection-5 per cent of above base cost in all cases. Running repairs-2.5 per cent of base cost in all cases. Interest-5 per cent depreciation, 7.5 per cent taxes, I per cent on variable cost. Auxiliary fuel-Anthracite plant, 15 per cent for boiler. Bituminous plant, 10 per cent for rebuilding fires. Labor-Anthracite, 10-hour power-One producer man; one ash handler " 60 $4.25 per day. 24-hour power-Two producer men; one ash handler— Bituminous, 10-hour power-One producer man; one helper; two 66 24-hour power-Two producer men; two helpers; two Sunday cleaners-$9.50 per day. (Figures) refer to number of quotations averaged. (+) Lehigh Valley, Reading White Ash. (*) Steam coal-Clearfield, Pocahontas, New River and Georges Creek. Gas coals-Westmoreland, Fairmont and Pennsylvania. CHAIRMAN FARRAND: Mr. Wells will now read the paper on The Future of the Gas Engine, by Mr. Lewis Nixon, of New York. Mr. Nixon is unable to be present at the meeting. Mr. Nixon's paper was presented by Mr. Wells, as follows: THE FUTURE OF THE GAS ENGINE The future of the gas engine is an immediate future. No claims need be made of what may be accomplished upon a visionary "some day." It is not a case of storage-battery perfection, of burning ashes, or of running vessels by projected energy from great central plants. The future of the gas engine rests upon results already accomplished, and it rests securely upon the solid foundation of greater economy and simplicity as compared with steam as a prime mover. Much will be done for the people of the United States if water-power throughout the country is utilized in their interests, and not monopolized; yet, if the whole of the power to be obtained from Niagara Falls were made use of there would be obtained only three times as much power as is now thrown away by our blast furnaces. Gas plants of the latest type on test develop 20 horse-power per hour at a fuel cost of one cent with gas producer plants using small-sized anthracite fuel. A conservative estimate is that the gas engine will cut in half the fuel bill required for a steam plant of the same power now, not in the future. The use of steam is prolonged for the present by the somewhat absurd claims made for the turbine, but it is only a temporary reliance and it must give way to a prime mover that does its work in every respect as well and at far less cost. The public, ever ready to acclaim a development for which intemperate claims are made, and being led to believe that a crank conversion leads to serious loss, has hailed the rotary and turbine engines as representing almost a revolution in steam engineering. For some purposes it has a distinct value so long as we must be slaves to the boiler, but the gas engine furnishes a mechanical emancipation proclamation and enables engineering progress to brush aside the boiler, and with it will go both reciprocating and turbine engines. We combine with the turbine the supreme economies in superheating and the use of more efficient and far more expensive condensation, which if used with the reciprocating engine will find the latter very far from a bad second. Had engineering arts progressed sufficiently to have enabled Ericsson to use with his hot-air engine such high pressures that the gain of 15 pounds by condensation could have been neglected, the internal-combustion engine would now have been in universal use and the flying machine a necessity of modern civilization. The development of the automobile has brought the gas engine to the front during the past seven years. When one sees this miracle of the twentieth century carrying persons in safety and comfort with the speed of railway trains upon the ordinary highways, under perfect control, which in a few years has educated thousands of men to understand perfectly its manipulation and adjustment, not one of whom could be trusted to run even a small steam plant, can there be a doubt as to a more general application? And in this connection one can see another factor of tremendous value to the human race. A short time ago a practical understanding of mechanics was looked upon by many as a vulgar though pardonable fad. To-day one sees men in all walks of life, not only with a full understanding of the workings of the gas engine, but able to grasp the finer points of the mechanics of transmission gear and structure generally, while men of wealth take pride in being able to "fix things" themselves. This closer touch with the mechanical arts will increase and can not fail to add to the comfort and happiness of mankind. For those who are not perfectly familiar with the gas engine let us use a homely illustration. If you place a coil spring upon the table and press it down, it will upon release push upward with nearly the same force as that which pushed it down. Now, if when compressed we could increase its stiffness it would push back with more force. If we compress air in a cylinder and at the bottom of the stroke heat this air, it will push the piston back with more force than was required to push it down. This, in simple illustration, is the principle of the gas engine. We draw in a charge, compress it, and, when compressed, inject gas, which is ignited by electricity or other means, and burning in the cylinder increases the pressure, or stiffens the spring, so that we get more work than was required to compress the air. Instead of burning our fuel under a boiler and losing in smoke, ashes, radiation, leakage, and so forth, we burn our fuel where it does the most good. An excellent showing of the comparison between steam and gas is obtained from the experiments of Mr. J. E. Dawson, of England. Tests were made with steam and gas plants, each of 250 horse-power. In the case of the steam plant it was found that of 1120 heat units contained in the fuel, 224 units are lost in radiation, flue gases, ashes, and so forth, and that 896 units appear in the steam generated. Of this amount 112 units are lost in condensation in pipes and 667 units in the exhaust, leaving 117 units for useful work in the engine. Taking out 17 units for engine friction, we have left 100 units of useful work out of 1120 in the fuel. A similar test with a producer plant shows that only 525 heat units of the producer fuel need be used to give 100 units of useful work. It must not be lost sight of that the best brains of the engineering world have been devoted to bringing the steam engine to the highest state of efficiency; while the gas engine, as a comparatively new prime mover, is not only immeasurably simpler, but in working tests is even now shown to be superior. But even if we get greater economy in less space and on less weight than with steam for the same power, we must be sure that the gas engine possesses durability under service conditions. Has it been used long enough and extensively enough to afford examples of durability? The gas-producer plant of the Erie Railroad at Jersey City has been in use for eight years and has never yet been relined with fire brick. In one producer the fire has never been out. In many cases gas engines are run for months without stopping. Can we find any steam plants of which the same may be said? The 1905 annual report of the Board of Public Works of Poughkeepsie, N. Y., in referring to the working of a 35-hp gas engine producer plant, says: "In the three months, January, February and March of this year, the steam plant pumping to filters used 223.59 tons of coal for 199.7 millions of gallons of water filtered, equal to 1.12 tons per million gallons. In the five months, July to November, inclusive, the gas plant used 78.16 tons for 317.8 million gallons filtered, equal to 0.24 ton per million gallons-a saving of 0.88 ton per million gallons. As an average of 63.5 millions were filtered per month, the difference in favor of the gas plant was 55.88 tons per month, costing in the shed $3.26 per ton or $182.16 per month." The total cost of the plant, gas-engine producer and pump, all installed, was $3,940, paid for by the saving of 22 months. Practically similar testimony can be obtained at hundreds of gaspower plants, large and small, throughout the world. The United States Geological Survey, after a careful examination of the possibilities of gas-making fuels, says officially: "Most of the American bituminous coals and lignites can be used as a source of power in a gas-producer plant. As indicated by comparative tests of fourteen bituminous coals from nine states, the power efficiency of these coals when used in the gas-producer plant is two and one-half times greater than their efficiency when used in the steam-boiler plant; or, in other words, one ton of these coals used in the gas-producer plant has developed on a commercial scale as much power as two and onehalf tons of the same coal when used in the ordinary steamboiler plant. The value of the results of these investigations is, of course, not limited to the coal-producing sections of the country, but extends through every state and territory where coal or other mineral fuel is used as a source of power. Thus in the New England states the coal is mined; but in the year 1900 the steam power produced through the consumption of coal and used for manufacturing purposes in these states cost approximately $50,000,000. The development of this power through the more efficient methods suggested by these investigations would mean a saving to the manufacturers in those states of $15,000,000 to $20,000,000 per annum. "As another illustration of the way these investigations influence the affairs of the nation as a whole, it may be stated that there were used on naval vessels in the United States in 1903 approximately 500,000 tons of coal, costing $2,500,000. If the future gas producer and gas engine could be substituted in our |