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wealth. He who gains wealth is invariably largely, even though usually indirectly, indebted for his prosperity to him who, without thought of pecuniary gain, is unselfishly devoting life and health to the attainment of scientific knowledge.

Science and the most perfect art can only flourish when assisted by wealth, and wealth can only come with least sacrifice to a country in which the true spirit of inquiry is awake and stimulating investigation. The more nearly men of the world and men of science are brought together, the more prosperous are all classes, and the happier and more contented are the people. We need all-observers, discoverers and inventors; explorers of all fields of research; students of Nature's facts, and codifiers of Nature's laws and teachers of all applied sciences, as well as workers in field, in workshop and in office. And we must have men who seek that highest honor which comes of the endowment of science philanthropists, like Stevens, and Rose, and Case, and a hundred others who are not, like these, members of our own profession, whose gifts have been the most splendid of charities and the most beneficent of all great work.

AN EXAMPLE.

As an illustration of the method in which advancement occurs, and as an example of the kind of work which remains for us to do, let us glance, very briefly, at the history of that greatest of modern triumphs of mechanism, the steam engine.

Away back, twenty centuries and more, in the dim past, among the first faint gleams of historic civilization, we see the germ of the invention which has done so much to annihilate space, and give man illimitable power over all the forces and treasures of nature-a toy in the museum at Alexandria. A toy, it remained many centuries, until, in the grand awakening of three centuries ago, its latent power was discovered, and Papin, and Worcester, and Leibnitz, and Huyghens each contributed a thought in the progress which they thus inaugurated. A hundred and fifty years ago, the "steam giant" was at work under the direction of the intelligent blacksmith and his comrade, the "tinker," doing much for the mining industry, but nothing elsewhere, and, hampered by ignorance and ill-cared for by his masters, wasting a vast deal of now utilized power.

Then came forward a genius of the brightest intellect, a mechanic, such as the world rarely produces-James Watt-and, adopting the truly philosophic method, the great master soon taught the mighty servant to do a thousand times more for the world, and to labor with wonderfully greater ease and economy. Watt first collected his facts. He dissected the model of the Newcomen and Calley engine, which had been placed in his hands for repair, ascertained the method of its operation, learned what were the advantages, and what the disadvantages, of that form of engine, discovered the cause

and extent of its losses of power and efficiency, and onee these were known, his grand intellect promptly devised remedies and improvements, and the steam engine of to-day is simply the steam engine of James Watt, in all its leading features and in all the principal details of design. Its steam-jacketed cylinder is Watt's; its parallel motion and its guides; its crank motion-although an invention usually ascribed to another-were invented by Watt, and the condensing apparatus, the expansion gear, the governor, and even that wonderful little instrument, the "indicator "-the engineer's stethoscope-all came down to us from the same source.

Watt learned the leading facts, and made the greatest modifications of plan, while it was reserved for our contemporaries to contribute the refinements of its design and of its manufacture, and to study the more deeply hidden principles of its philosophy, and to determine more definite rules for its construction and management.

Those of you who have been familiar with the design and construction of steam engines during the past twenty or thirty years,* and those of you who have been for a generation past accustomed to handle this miracle of art, will remember, as I remember well, how we learned, at a very early period in our experience, several cardinal points of practice which were very strongly impressed upon us. We soon learned by experience that efficiency was gained only as we learned to handle higher steam with properly adjusted expansion, to work our engines up to higher piston speeds, to cushion heavily when we had large clearance, to reduce that clearance to a minimum, to adjust the size of our engine to its work, and to determine the point of cut-off, under proper conditions otherwise, by the governor. †We learned that the now well-known "American Automatic Cut-off Engine," with its high steam and moderately large expansion, as exemplified by the "Corliss Engine," which is now built all over the world, was the representative of best general practice.

But we were not satisfied. Twenty years ago we began to understand that we had yet to perfect the philosophy of the steam engine, and that it was still apparently far from perfect efficiency. We then discovered that while our best engines were consuming from twentyfive to thirty pounds of dry steam per horse-power per hour, the mechanical equivalent of the heat supplied to the steam in the boiler was sufficient to give about a horse-power per each two pounds of highpressure steam per hour, and hence that we were utilizing but onetenth or one fifteenth of the heat we were paying for when we settled our coal bills.

* Report on Machinery and Manufactures at Vienna, 1873, by R. H. Thurston, etc., etc., Wash., 1875. Progress of the Steam Engine.

History of the Growth of the Steam Engine; International Series; N.Y., 1878, p, 473.

Next, we found that, owing to the fact that we cannot practically expand down to a pressure lower than that due approximately to the temperature of surrounding bodies, that we must therefore discharge heat unutilized, that the larger part of this waste is unavoidable and that an engine, perfect mechanically and working within the maximum usually practicable limits, must waste three-fourths, and can return useful effect from but one-fourth of the heat supplied, thus placing the practical limit under known conditions at about eight or ten pounds of steam per hour per horse-power.

And here we stand to day with the steam engine mechanically almost perfect, yet with a theoretical economy of about eight or ten pounds of steam per horse-power per hour while consuming actually, in the best examples, over fifteen, i. e., with an efficiency of sixty or seventy per cent.

In hot-air engines we are not making much more rapid progress, and our field of promise seems to be still in the improvement of the steam engine.

We are slowly learning other facts. We know that the great obstacle in the way of attaining nearly theoretical efficiency is the transfer of heat from the steam to the exhaust side by initial condensation and re evaporation; we are discovering that high speed and steam jacketing tend to lose their efficiency at extremely high pressure with wide ranges of expansion, that it seems possible to reach a point in steam-jacketed cylinders at which lower speed may tend to secure efficient working of the steam; that with well-jacketed cylinders we may get good performance, as we to-day judge it, with slow pistons ; that we have better work claimed to-day for single than for "compound" engines; the minimum yet reached under fair conditions for economy being stated to be by experiment as 1.54 is to 1.75, while, assuming the very best conditions for each, it seems certain that both types should give about equally good results.

*

Here is where we stand to-day, and it is from this point that we are to work forward. We need to collect more facts by means of carefully-devised experiments like those of Hirn and Hallauer abroad, and of Emery, and of the Navy Department at home; we need careful and systematic study of the results, and, finally, the determination of the laws of steam engine efficiency as affected by steam pressure and temperature, rates of expansion and compression, character of steam jackets, rate of piston speed, and every other circumstance influencing economy.

It would seem

* Abstracts of Papers, No. 1602; Proc. Brit. Inst. C. E. Vols. LIII, LIV. that where slow piston-speed is demanded, as usually with pumping engines or where two cylinders are needed as with marine engines, the "Compound " engine is unmistakably the best; while where high-speed engines are permitted, as in mills, the single-cylinder may still hold its own in this competition.

THE ETHICS OF CO-OPERATION.

This, and such as this, is work for some of us, and such work is to be done in every one of the many branches of industry which are here represented. And this, too, is a kind of work in which all can take part, fully confident that the good work shall benefit all and shall injure no one member of the human race.

That great member of our profession, that engineer who has become the greatest philosopher of our age, or indeed, I think, of any age-Herbert Spencer-in his last and culminating work, the "Principles of Morality," shows us, in his "Data of Ethics," how the natural evolution of the noblest conduct, as traced by the scientific mind of the moralist, accords perfectly with that dictated by the noblest minds and best men of all times, as well as by the truest Christian philosophers.

The great moralist shows us that naturally right conduct-scientifically correct conduct-toward which we are constantly progressing, as civilization and intelligence advance, as well as righteous conduct, such as the best of men admire and teach, leads to the care of self, of family, of friends, of fellow-citizens and of mankind, by the individual and by society, in such a manner as shall, at the same time, most perfectly protect the interests of each individual, while to the least possible extent injuring his neighbor in the process; and he further shows that perfect conduct, whether considered scientifically, or morally and religiously adjudged, will be attained when we shall have learned to fully protect and preserve self and family, and to individually attain length of life, perfect health and unalloyed happiness, while yet, in the same degree of completeness, promoting the same end as sought by each of our neighbors and by society at large. In other words, when we shall have become sufficiently intelligent, and sufficiently good, to exhibit "perfect conduct" in all our relations, we shall find that the promotion of mutual welfare is, in the highest degree, consistent with-and that it is only consistent with -the highest, the most perfect system of mutual co-operation and mutual aid in all the truest and highest aims of life. Then, this point reached, life will really become "worth living," and mankind. will occupy a place very, very little lower than the angels."

This, then, is the fundamental rule of action, and these are the principles which, we may hope, will always guide the American Society of Mechanical Engineers in every effort to aid the profession and to benefit the world.

DISCUSSION.

Mr. C. E. Emery-I was not aware that it was definitely settled that the single engine was doing better than the compound.

Prof. Thurston-The fact on which I based the statement was that Farcot has recently built an engine with which he is said to get a horse power with a pound and a half of coal per hour, and that the Woolf engine has given a minimum of about one and seven-tenths. The best records I have found of the compound engine are thus a little better than the best records I have found of the single. Sometimes one engine comes out a little ahead, and sometimes the other engine. It is probable that Farcot also had the best boiler he could construct, and a peculiarity of the engine, as I remember now—you will find a reference to it in the abstracts published by the British Society of Civil Engineers-is that he reduced his clearance to one per cent., which is the lowest figure for clearance that I have in mind, and that has something to do, no doubt, with this economy.

There is another point that I presume may be referred to. I have stated that possibly a lower piston speed might, in some cases, produce a better economy than has hitherto been produced. An engine has been built by one of the best-known builders in this country, and it has given a wonderful result in economy at a fair speed. I am speaking now of a pumping engine. The same engineer has also built an engine which has given a wonderfully low result at very low speed. Now, another engineer, whose name I am not at liberty to mention, but whose engines I have seen, has built an engine which, with piston speed of only ninety feet a minute, has given a high duty, and, as one peculiarity there is that he has used higher steam pressure in his jackets than in his cylinders. His is a single cylinder engine. If you secure yourself against this internal condensation, you are pretty independent of piston speed; although, on other accounts, I should prefer myself to use high piston speed. Another fact that bears in the same line-we have had a trial of an engine recently, which is carrying unusually high steam. The builders say they will guarantee a pound and a quarter of coal to the horse power. It was found that the amount of the condensation in the high-pressure cylinder was something tremendous. The only solution of that curious problem to my mind is, that the heat could not go through the jacket walls fast enough to supply the losses due to condensation. The steam, striking into a cold cylinder, had its heat taken out by condensation. If that engine had run slower, it might have given a better economy. The actual result was not at all encouraging. Instead of getting one and a quarter pounds, we have two and seven-tenths pounds, as the consumption of coal, and about two pounds of the combustible part of the fuel, per horsepower and per hour.

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