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As abundantly appears in the preceding pages from the testimony of numerous engineers, Mr. Holley felt a profound interest and exercised an important influence in the progress of technical education in this country. Not only his faithful work as an instructor,
but numerous public expressions of his views, bear witness to his zeal and wisdom in this field. As one of the most impressive of these utterances, the following address delivered at Washington, D. C., February 22, 1876, before the American Institute of Mining Engineers, of which Mr. Holley was at that time President, is here reproduced. It is, at the same time, a good example of the eloquence and logical force with which he handled themes of this character.
THE INADEQUATE UNION OF ENGINEERING SCIENCE AND ART.
The application of scientific methods to the investigation of natural laws and to the conduct of the useful arts which are founded
upon them, is year by year mitigating the asperity and enlarging the outcome of human endeavor. More notably, perhaps, are these the facts in that system of productive and constructive arts of which Engineering is the general name. In metallurgical engineering especially, within the period of our own recollection, how rapid has been the rate and how wide the scope of progress—the scientific discovery and mining of metalliferous veins; the economical separation and reduction of ores of every grade; the production and regulation of high temperatures; the varied improvements in the manufacture of iron, in saved heat and work, in uniformity and range of products; and most important of all, the creation and the utilization, to be counted by the million tons a year, of the cheap constructive steels !.
Wonderful as this range and degree of development may appear to the public eye, the close and thoughtful observer must nevertheless conclude that neither the profession nor the craft of engineering may congratulate themselves too complaisantly, but that they should rather acknowledge to each other the embarrassing incompleteness of the union between Engineering Science and Art.
There is a small but most truly scientific and most truly practical school of philosophers whom we may designate as original investigators---men who come close to nature, who search into first principles, and who follow in all things that scientific, and therefore fruitful, method by which the relations of matter and force are discovered, classified, and brought within the reach of practice. These wonderful men do not indeed create the laws of nature, as they sometimes almost seem to, but they go up into the trembling mountain and the thick darkness, and bring down the tables upon which they are written.
There is a large class of men whom we may designate as the schoolmen, a class popularly, and, to a great extent, correctly recognized as the scientific element of human progress; men who are learned in the researches and conclusions of others, and skilled in reasoning or speculating from these or from abstract data upon the certain or probable results of physical and chemical combinationg.
And there is the great army of practicians, almost infinite in its degrees of quality, ranging from the mere human mechanism by which mind lays hold of matter and force, through all the grades of practical judgment and power—an indispensable link between nature's forces, as the philosopher thinks they are, and nature's materials, as the practician knows they are.
As the art precedes the science (however the science may afterwards revolutionize the art), let us first consider the matter from the artisan's—the “practical ” man's standpoint. While every day's experience could teach him a more helpful lesson, it could hardly teach him one of greater general importance than that the men who speculate, from second-hand data, upon the probable results of combinations of forces and materials, are not the men who can best make these combinations in practice, who intuitively know all the concealed pitfalls, such as friction—that trick of nature, which, like the thousandth part of phosphorus, alters all the conditions of use in ironnor are they the men who can determine the completeness of these combinations, or read the record of their results, as in the character of a flame, in the feeling of a refractory mixture, in the behavior of a metal under treatment; nor are they the men who, by familiarity with objects and phenomena, are best fitted to pursue that original investigation which is the foundation of even theoretical progress. The expert who delights to call himself “practical,” is honestly
amazed at the attempts of experts of school-graduation who have not been graduated in works, to solve the engineering problems of the day. And from his stand-point there are numerous and conspicuous illustrations. While metallurgists are still disputing over the nature and sequence of reactions in combustion and reduction, the practical iron-smelter has felt his way from the barbarous practice of a century ago, to the vast and economical production of to-day. The attainment of powerful and sufficiently hot blast by means of waste heat, the adaptation of shape and proportion of stack to different fuels and ores, labor-saving appliances and arrangements—all these have grown out of the constant handling, not of books, but of furnaces.
Proceeding upon a chemical knowledge little superior to that of the average schoolboy, Bessemer developed his revolutionary process. Not knowing for years that the combustion of silicon or of manganese are the chief sources of the necessary heat, ignoring the fact that not alone the reaction but the presence of manganese is a cause of soundness and malleability in steel, magnifying the hypothesis that silicon should promote soundness, instructing his licensees to avoid all irons containing above 0.02 per cent. of phosphorus, and sharing the ignorance of the whole metallurgical profession as to the sequence of reactions in the converter, and the probability of changing their character, Bessemer and his followers, during the first 15 years of their practice, nevertheless brought this difficult art, which the metallurgical schools call a chemical art, to a high degree of commercial success, and this in the absence of any metallurgical change or chemical improvement whatever, in the treatment of the metal. During all this time, there was almost no literature of the Bessemer manufacture, and no instructor save that grim sphynx the converter, and the well-nigh inscrutable process. It was a hand-to-hand fight, involving mechanical details, refractory linings, celerity of operations, regularity of melting and conversion, and economy of labor. With every fact written in his book, the closeted scientist could no more adequately prescribe the practical conditions of improvement, than could the student in optics specify in words and formula the glory of an Italian sunset.
Here is a cupola-furnace, an old and exceedingly simple device; but one may know all the laws of combustion and Auxing that are written in the encyclopædias, and yet fail to change its working at will, or fail to detect the coming change, until by long familiarity the phenomena reveal themselves as it were instinctively. One may have learned every law of the reaction of oxides and fluxes upon a refractory material, yet until his practiced hand and eye and ear can nicely detect its physical qualities and measure the results of new ingredients and temperatures, he may wander for years in a maze of uncertainties. Notwithstanding all our previous knowledge about the inevitable combustion of carbon and oxygen in the presence of heat enough to ignite them, the Siemens-Martin process, both in its calorific and in its metallurgical aspects, was as purely unpractical as the direct utilization of sun-heat is to-day, until after years
of patient observation, not chiefly by scientists, but by men unacquainted with books, and knowing nothing at second-hand, innumerable small increments of improvement at last produced a sufficient temperature in a durable furnace.
In the development of machinery, the same history is repeated. The proportions of parts, in fact, the modern formulæ themselves are derived from the study of innumerable experiments. The adaptation of machinery can only be perfected by him who, as it were, enters into it, making it an incarnation of himself. This enlargement of a man's organism is most strikingly illustrated in the locomotive. Oliver Wendell Holmes has happily described this putting of his life into his “shell” boat, his every volition extending as perfectly into his oars as if his spinal cord ran down the centre of its keel, and the nerves of his arms tingled in the oar-blades. The
thoughtful locomotive-driver is clothed upon, not with the mere machinery of a larger organism, but with all the attributes of a power superior to his own, except volition. Every faculty is stimulated and every sense exalted. An unusual sound amid the roaring exhaust and the clattering wheels, tells him instantly the place and degree of danger, as would a pain in his own flesh. The consciousness of a certain jarring of the foot-plate, a chattering of a valve stem, a halt in the exhaust, a peculiar smell of burning, a sudden pounding of the piston, an ominous wheeze of the blast, a hissing of a waterguage-warning him respectively of a broken spring-hanger, a cutting valve, a slipped eccentric, a hot journal, the priming of the boiler, high water, low water or failing steam—these sensations, as it were, of his outer body, become so intermingled with the sensations of his inner body, that this wheeled and fire-feeding man feels rather than perceives the varying stresses upon his mighty organism.
Mere familiarity with steam-engines is not, indeed, a cause of improved steam-engineering, but it is a condition. The mechanical laws of heat were not developed in an engine-house, yet without the mechanism which the knowledge derived through this familiarity has
created and adapted, the study of heat would have been an ornamental rather than a useful pursuit. So in other departments : when one can feel the completion of a Bessemer“ blow” without looking at the flame, or number the remaining minutes of a Martin steel charge from the bubbling of the bath, or foretell the changes in the working of a blast-furnace by watching the colors and structure of the slag, or note the carburization of steel by examining its fracture, or say what an ore will yield from its appearance and weight in the hand, or predict the lifetime of a machine by feeling its pulse; when one in any art can make a diagnosis by looking the patient in the face rather than by reading about similar cases in a book, then only may he hope to practically apply such improvements as theory may suggest, or to lead in those original investigations upon which successful theories shall be founded.
These are the conclusions of the practical ” man, and they are none the less true because they are not the whole truth. That they are too little considered by the schoolmen and the graduates of schools is also true, but, happily, less conspicuously so as the years advance.
The evil consequences of this mistake develop themselves in various ways. The recent graduates of schools do not, indeed, expect immediate positions of responsibility and authority, but they often demand them after too short a term of object-teaching. Perhaps the greatest advantage of their scientific training is that they can learn from objects and phenomena faster than can the mere workman, who, although full of the elements of new and useful conclusions, lacks, if I may so say, the scientific reagent which precipitates the rubbish and leaves a clear solution of the problem. It is, however, true-in the iron-manufacture, perhaps, especially true that men of wide learning and of great mental dexterity, unless they have studied at least as many years in the works as they have in the school, do not successfully compete for the desirable places with the men that have come up from the ranks. Narrow, unsystematic, and fruitless of new results as his knowledge may be, he who has grown up steadily from the position even of puddler's helper, will be selected to take the manager's post in preference to him whose reputation is founded solely on the school.
Nor does this prove, as the schoolmen too often believe, that the owners and directors of metallurgical enterprises are always unappreciative of scientific culture. It rather proves that the lowest functions, as in the case of pure humanity, must first be considered—that