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The Pamphlet Collection of Sir Robert Stout: Volume 33

[article]

The subject I propose to consider to-night is a very important and difficult one, and I fear that within the short limit of an hour's lecture it will be impossible to render it justice. However, I shall endeavour to go into the matter as simply as possible, pointing out some of the more prominent evils in our present system of educating engineers, and suggesting means for their removal.

With regard to the importance of the profession of the engineer, I think no doubt can be entertained by any thinking person. The works of the engineer are found everywhere around us; wherever we go, and whatever we do, our comfort and safety depend upon him. Before our public lands can be rendered available for sale or settlement, the topographical engineer is needed to execute surveys extending over vast tracts of country, to mark out allotments, choose sites for townships, indicate lines of roads, and delineate the various features of the country. Then the road engineer is called in to open up practicable lines of communication, to bridge rivers, cross fathomless swamps, and supply a means whereby the produce of the land may reach the market, and the commodities of other countries find their way to the home of the settler. Until this be done, the most fertile district will remain practically useless to the community in general.

As population increases, and the resources of a locality become more fully developed, modes of locomotion and transport speedier than horse traction are demanded, and we find the engineer again at work, constructing railways.

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His work does not end here. We soon require supplies of water, and the engineer is called upon to construct reservoirs, to lay down miles of pipes, to reticulate our towns, and bring the waters of mountain streamlets to our very doors.

Sewerage naturally follows water supply, and the engineer is required to construct drains and sewers, whereby our towns may be kept clean and dry, and all matters offensive to the senses or injurious to the public health removed at once to a distance from the dwellings of men.

Then our shipping needs harbours and docks for its reception, and these must be supplied, with various appliances for the purpose of loading and unloading vessels, and storing merchandise. Our rivers, too, will require improvement, and our towns and cultivated lands must be protected from floods. This involves the deepening of channels, the construction of embankments, and the execution of other works too numerous to mention.

Inland navigation gives further scope for the practice of engineering, and by the removal of obstructions, the construction of weirs and locks, the engineer causes streams which previously had conferred no appreciable benefits upon the districts through which they ran, to become most efficient highways for the conveyance of merchandise.

In localities where no suitable rivers exist, canals have to be made, and the construction of these necessitates the employment of no small amount of engineering skill.

The artificial lighting of our towns, the construction and management of gasworks, lies also within the domain of the engineer; and manufactures of all kinds—together with the operations involved in mining for gold, coal, iron, copper, and other minerals—continually require him to design and construct the various engines and machines necessary for their successful prosecution.

In fact, there is hardly any object, any commodity, anything we use, which does not in some way render us dependent upon the engineer; and this being so, it is clear that the importance of the profession is great indeed

Looked at from a monetary point of view, the engineering profession cannot fail to excite great interest when it is remembered that something like £20 per head for every man, woman, and child in this colony has already been invested in engineering works.

Suppose now, for one moment, that our engineers, through want of proper education, be not competent for the work they page 30 are called upon to perform, what will be the result i Our roads impassable, our railways a failure, our reservoirs bursting, our rivers overflowing their banks and destroying life and property, our manufactures languishing, the advancement of the country retarded, possibly even its solvency endangered.

Before discussing different systems of engineering education, it will perhaps be well to give an example indicating the nature of the engineer's work, and illustrating the various demands constantly made upon his judgment and skill.

Let us take a work of frequent occurrence, say a large bridge across some important river that has hitherto formed a bar to the traffic passing between two districts.

The first operation will be the collection of statistics. A careful investigation must be made as to the probable traffic across the projected bridge. Valuable data may be obtained from the Registrar-General's office, from local records, or from actual observation. The result of this calculation, viewed in connection with the estimated cost of the structure, will enable the engineer to judge whether the proposed work is likely, in a commercial sense, to pay.

The next step will be to determine the most suitable site for the bridge. The river must be examined, its floods observed, its banks surveyed, borings must be made in search of a good foundation; and quarries of good stone, of lime, and other material needed in the execution of the work, must be diligently sought.

The engineer will probably discover several promising sites, each one possessing some particular advantage over the others, and the ensuing process of weighing one recommendation against another, and arriving at a correct decision between various conflicting considerations, must necessarily be such as to tax to the utmost the greatest skill and the most carefully trained judgment.

The site fixed, the next step will be to design the structure, and first of all a choice must be made as to material. Stone, brick, iron, and timber each present certain advantages, and their relative cost and durability must be carefully considered before making a final selection.

Suppose the decision to be in favour of stone supports or "abutments," and an iron superstructure. In designing the abutments, an accurate knowledge of the supporting power of the substratum, and also of the horizontal pressure or thrust of the earthen embankment leading up to the bridge, will be needed. Should any error occur at this stage, the result will page 31 be either that a large quantity of valuable material will be wasted, or, on the other hand, the very existence of the structure may be imperilled by the lack of strength of its most vital parts.

The superstructure may consist either of a horizontal girder, so arranged as to impose a vertical pressure only on the abutments, or of an arch. In either case, the designer will first need to determine the greatest probable load the bridge will be required to sustain; then, by a somewhat complex mathematical investigation, he will discover the magnitude and direction of the various resulting stresses or forces acting upon all the different parts of the structure; and, finally, he must so arrange all the details as to obtain a sufficiency of strength with a minimum of material and workmanship. This work will demand for its successful completion—first, a thorough knowledge of the laws of force, as investigated by mathematicians; and, second, an equally thorough knowledge of the physical properties of the material, the process of its manufacture, the various forms in which it reaches the market, and the most convenient and efficient method of uniting together the integral portions of the structure.

The flooring or deck of the bridge, the handrail and other matters of minor importance, must lastly be arranged; and a judicious treatment of these details, though perhaps adding nothing to the stability of the structure, will greatly conduce to the comfort and convenience of travellers.

A carefully written description, called a specification, should accompany the plan. This is by no means an easy part of the work, as every omission or mistake is sure to turn up during the execution of the work, and become a fruitful source of annoyance and expense.

The operation of "taking out quantities" will next engage the attention of the engineer. By an intricate application of the science of mensuration, he will determine the number of cube yards of masonry, tons or pounds of ironwork, cube feet of timber, etc., &c.; and then his knowledge of the commercial value of various descriptions of material will enable him to estimate the total cost of the structure.

Tenders are now called for, and the contract for the execution of the work is let. The superintendence of the work immediately demands attention. Should the contractor prove an honourable man, anxious to fulfil his obligations thoroughly, all will go on smoothly; but if, on the other hand, he should be desirous only of his own emolument, and careless as to the page 32 quality of the work done, the position of the engineer will become most difficult. None but those who have actually been connected with the execution of important works can form an adequate idea of the numerous ingenious artifices employed by dishonest contractors in order to substitute inferior material and workmanship for that specified, and of the incessant vigilance requisite in order to detect and frustrate such attempts.

The work proceeds, and in due time is completed; but in almost every case small alterations are needed, errors in the specification are discovered and have to be rectified, and extras require to be authorised and paid for in a manner equitable both to the client and the contractor.

From this example—which is, I think, a fair one—it will be evident that the profession of civil engineer is most onerous, and makes very exacting demands upon the forethought, skill, judgment, and care of those who follow it.

The mechanical engineer usually finds an outlet for his skill in acting as contractor to the civil engineer for metal work, and as manufacturer of machinery. In this latter branch he has the great advantage of carrying out his own designs, and consequently knows nothing of the difficulty and anxiety of superintending contract work. Great demands, however, are made upon his ability and care in other directions. He needs extensive experience in the manipulation of metals, and must practise a most thorough system of keeping accounts, so that every portion of material used, and every hour of the workman's time, may be debited to the proper piece of work.

Although usually engaged in copying, with but slight modifications, well-known designs, he is not unfrequently called upon to devise novel contrivances demanding considerable inventive skill. Beside, a natural and laudable ambition will incite him to leave the beaten track, and improve upon the works of his predecessors; hence he will need considerable scientific knowledge to guide him in his investigations, to prevent him from wasting his time upon ideas which, being contrary to the established laws of nature, must necessarily fail, and to save him from the too common error of mistaking mere modifications for essential improvements.

The amount of skill and training exhibited by our engineers varies very much indeed. They may be divided into several great classes, not sharply defined, but passing by insensible gradation one into the other.

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First—We have men of thorough education, both in science and actual work, understanding principle as well as detail, excellent in theory, unimpeachable in practice. These naturally take the highest place, and are without exception men of refinement and culture, upon whom for me to comment would be simply impertinence.

Second—A large class consisting of men possessing much practical skill, but unfortunately deficient in theoretical knowledge. So long as these follow in the footsteps and copy the works of their more scientific brethren, they do not fail to give satisfaction. But when they attempt to strike out in a new direction, and produce something original, they are in constant danger of falling into most serious errors through not properly comprehending scientific principles.

For many kinds of work such men are eminently adapted. For example, in road construction there is no need of accurate theoretic knowledge, but wide scope for the exercise of sound judgment, supplemented by that acquaintance with the properties of materials which long experience alone can give. In the supervision of works designed by abler men this class of engineers prove themselves very useful. Their great practical experience in the execution of work renders them most reliable and trustworthy; while so long as they can understand an ordinary drawing and specification, and discriminate between good and bad work, their ignorance of the scientific principle upon which the efficiency of the structure or machine represented by the drawing depends is a matter of no consequence.

Third—We occasionally find gentlemen possessed merely of theoretic knowledge entering the engineering profession, and endeavouring to compete with other engineers. Their knowledge of principles is most thorough, but they lack practical acquaintance with matters of detail; and lacking this, they fail. Most likely they could give an excellent description of the great Britannia bridge, but would hopelessly break down if engaged in the very ordinary task (to a practical man) of constructing a common log culvert.

The professional career of such is generally but short They retire discontented with themselves and with others; and the further evil is that they bring scientific knowledge into disrepute with less educated men, who look upon them, and by implication upon all science, as a mere sham; and so the great breach between theory and practice, instead of being bridged over, is widened.

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Last of all, there is a class of men of whom, perhaps, the less said the better. They glory in the title of "practical," they hate theory, they despise science, knowledge of any sort they think beneath their notice, they consider they know everything and that wisdom will die with them; and no matter how great another engineer's attainments may be, if he happen to differ from them in the slightest particular, they put him down as a mere theorist, and declare him to know nothing at all about the matter.

These men are the bane of engineering work, and anyone having such a man in the capacity of workman or contractor under him will know it to his cost. Nothing is right. The practical man knows everything, and the engineer knows nothing; the practical man buttonholes you to make you admit you are but a charlatan, an impostor, and will put forward the most preposterous ideas, utterly contrary to the firmly-established principles of science, forcing them down your throat as the result of his long experience, ten thousand times more valuable than any mere theory. I have known, have seen, these practical men, as no doubt many of my hearers have, the most ignorant but at same time conceited beings that can be imagined, and constantly making the most atrocious failures; but however gross their blunders, they never seem to see them, but continue to puff their own ability and waste the capital of their misguided clients.

The opinion that there is a necessary and inevitable discord between engineering theory and practice seems to have taken deep root in the minds of many men. "Very good in theory, but will not do in practice," is a phrase in constant use, and no one can come in contact with the majority of engineers without perceiving that they regard theory as utterly useless, and experience as the only reliable guide. We do not find astronomers behaving in this way—they do not inveigh against the law of gravitation, or hold up the parallelogram of forces to ridicule; on the contrary, they uniformly testify that the closest agreement exists between their theoretic calculations and actual observations; and if this be the case in astronomy, why not in engineering? The truth is, that in engineering, as well as astronomy, experience and theory are at one; and if there be any apparent contradiction, it is either because some error has been committed in the theoretical investigation, some essential term or factor omitted, or else the conclusions which we dignify with the name of experience are hasty and erroneous generalisations, liable to be greatly modified, if not completely page 35 reversed, by a more thorough examination of the facts of the case.

Perhaps you may remember an anecdote related by Mr. Ellery, in one of his lectures, of a captain of a vessel who experienced great difficulty in navigating his ship, owing to the chronometer having broken down. When asked why he did not verify his position by lunar observations, he replied that he tried two, one of which placed him in the centre of Sahara, and the second in some other equally impossible place, and that, therefore, he concluded that lunar observations were not of much account.

So with many engineers. They attempt to apply scientific principles which they have never thoroughly mastered, they omit some vital factor, and consequently their conclusions are vitiated; and then, like the captain with his lunar observations, they conclude that theory is an utterly unreliable guide. Very many instances of this particular error have come under my own observation.

The following example will serve to exhibit some of the evils flowing from the imperfect acquaintance with scientific principles commonly found amongst professional men. The security of life and property in a certain district depended upon the efficiency of a particular water channel. Four engineers were consulted as to its discharging power; two affirmed that it was ample, the other two were equally sure that it needed to be six or eight times as large. Each opinion was given after a most careful examination of the facts of the case, and the problem was one admitting, or rather requiring, a purely mathematical investigation. You will, I think, admit that there must have been great ignorance on one side or the other, especially when it is remembered that this subject has long ago been thoroughly discussed by scientific men.

Again, look at the number of absurd inventions, in prosecuting which men of great practical skill, excellent knowledge of detail, and capability of judging material and workmanship, have, for want of acquaintance with scientific principles, spent many years, or even their whole lives, in following visionary ideas which the slightest scientific examination would have exploded. Instances of the most egregious waste of time, skill, and money, for want of a very little accurate theory, are only too common in this colony as well as in the mother country.

Before leaving this part of my subject, allow me to read an extract from one of Professor Rankine's works, and to assure page 36 you that his view of the case is by no means exaggerated, and that examples of the evils to which he refers are to be found almost everywhere.

Rankine says—"It is on the practice of mechanics and engineering that the influence of the great fallacy is most conspicuous and most fatal. There is, assuredly, in Britain no deficiency of men distinguished by skill in judging of the quality of materials and work, and directing the operations of workmen—by that sort of skill, in fact, which is purely practical, and acquired by observation and experience in business. But of that scientifically-practical skill which produces the greatest effect with the least possible expenditure of material and work, the instances are comparatively rare. In too many cases we see the strength and stability, which ought to be given by the skilful arrangement of the parts of a structure, supplied by means of a clumsy massiveness, and of lavish expenditure of material, labour, and money; and the evil is increased by a perversion of the public taste, which causes works to be admired, not in proportion to their fitness for their purposes, or to the skill evinced in attaining that fitness, but in proportion to their size and cost.

"With respect to those works which from unscientific design give way during or immediately after their erection I shall say little, for with all their evils they add to our experimental knowledge, and convey a lesson, though a costly one. But a class of structures fraught with much greater evils exists in great abundance throughout the country, namely, those in which the faults of an unscientific design have been so far counteracted by massive strength, good materials, and careful workmanship, that a temporary stability has been produced, but which contain within themselves sources of weakness obvious to a scientific examination only, that must inevitably cause their destruction within a limited number of years.

"Another evil, and one of the worst, which arises from the separation of theoretical and practical knowledge, is the fact that a large number of persons possessed of an inventive turn of mind, and considerable talent in the manual operations of practical mechanics, are destitute of that knowledge of scientific principles which is requisite to prevent their being misled by their own ingenuity. Such men too often spend their money, waste their lives, and, it may be, lose their reason, in the vain pursuit of visionary inventions, of which a moderate amount of theoretical knowledge would be sufficient to demonstrate the fallacy; and for want of such knowledge many a man, page 37 who might have been a useful and happy member of society, becomes a being than whom it would be hard to find anything more miserable.

"The number of those unhappy persons, to judge from the patent lists and from some of the mechanical journals, must be much greater than is generally believed. The most absurd of all their delusions, that commonly called the perpetual motion—or, to speak more accurately, the inexhaustible source of power—is in various forms the subject of several patents in each year.

"The ill success of the projects of misdirected ingenuity has very naturally the effect of driving those men of practical skill who (though without scientific knowledge) possess prudence and common-sense to the opposite extreme of caution, and of inducing them to avoid all experiments, and confine themselves to the careful copying of existing successful structures and machines—a course which, although it avoids risk, would, if generally followed, stop the progress of all improvement."

The engineering profession is usually entered in one of two ways. Either the youth is articled for a term of years to an engineer in practice, or else he is placed at an engineering college where he attends lectures upon various scientific and professional subjects. At the close of his apprenticeship, or curriculum, he is supposed to be qualified to undertake work on his own responsibility. Each of these methods is, in my opinion, exceedingly defective, and I maintain that a judicious combination of the two is necessary in order to produce thoroughly competent engineers.

When a young man is articled to an engineer in practice, he is first employed in tracing or copying drawings, and other merely mechanical or routine work. After a time, if he show intelligence and aptitude, he is required to make working drawings of various structures and pieces of mechanism, these drawings being, in most instances, little more than fair copies of rough sketches supplied by the engineer. He is also afforded opportunities of inspecting works in progress. This constitutes the whole of his education. He cannot help learning how work is done, but he never learns why it is so done. The engineer invariably considers that the pupil receives full value for his premium in having the run of the office and access to the various drawings and specifications to be found there, and never for one moment dreams that it is any part of his duty to supply direct instruction in the principles of page 38 engineering science. The pupil, on the other hand, is well content with a system which imposes hardly any strain upon his intellect, and is only too apt to fall into the almost universal delusion that experience is everything, and theory of no consequence at all.

At this stage, I cannot but animadvert upon a practice which obtains with certain men professing to be engineers, but having no practice. Such persons open offices, insert magniloquent advertisements in the daily papers (a most unprofessional proceeding), and then endeavour to induce young men to pay high premiums for the privilege of becoming articled pupils. The unfortunate youths at first imagine in their ignorance that all is well, but before their apprenticeship is over they discover that they have been the victims of a most iniquitous deception, and that as far as engineering education is concerned they are no better off than when they commenced.

Gentlemen educated solely by being articled to an engineer almost invariably become members of that class of engineers who possess abundant practical knowledge, but make most egregious blunders in matters of a theoretic or scientific nature; excellent as they are in the execution of work, their designs are either mere copies and adaptations of existing structures, or, if they attempt anything novel and original, are characterised by a supreme disregard of the most firmly established scientific principles.

The second method of entering the profession is by passing through a course of systematic study at an engineering college. Those who adopt this route receive incalculable benefit from the mental discipline necessarily involved. They obtain a thorough insight into those fundamental principles which form the basis of all sound practice, they form orderly and logical habits of thought, but, unfortunately, they are very apt to despise small matters of detail and routine.

In my position of Lecturer on Engineering at the University of Melbourne, I have had many opportunities of observing this defect; many of the ablest among the students seem quite content with mastering the leading principles, and exhibit a marked indifference and disregard of detail. They thus are in great danger of becoming totally unfitted for attending to the minutiæ of everyday practice, and expose themselves to the ridicule of those who, with far less knowledge of principles, possess this indispensable acquaintance with detail. Great disappointment is not unfrequently felt by gentlemen who find, page 39 at the close of a curriculum extending over two or three years, that they still stand in need of many things in order to fit them for the practice of their profession. But it should be remembered that an apprenticeship extending over five or seven years is needed by many handicraft trades; and if an artisan's education requires so long a period, surely it is absurd to expect to obtain a complete grasp of a difficult profession in two, or even three, years. The University course cannot possibly do more than lay the foundation, upon which a super-structure of sound practical experience must afterward be raised, by means of long continued observation and study; and those who look upon their university studies in this light, and are careful to give both theoretic principles and practical details due attention, will not fail to confess that such a course is a most indispensable preliminary to the intelligent and progressive practice of engineering.

The judicious combination of practical and scientific training for a young engineer presents a problem of great difficulty; but, with all due deference to the opinions of the many able men who have thought and written upon this vexed question, I would venture to suggest the following course as affording, upon the whole, a tolerably satisfactory solution :—First, then, let the lad have a sound school education, suitable to the position in society he is expected to fill, and having, at the same time, a bias or leaning toward the pursuit which he is to follow. For example, his attention should be given to mathematical and scientific, rather than to classical or historical, studies. At the age of fifteen or sixteen he ought to be sufficiently advanced to pass such an examination as that for matriculation at the University of Melbourne. He should then devote at least one year to studies of a mathematical nature. Ample time must be given to algebra, Euclid, and plane trigonometry, and the greatest care should be taken in order to insure that the student may not only commit the principles of these various sciences to memory, but also thoroughly comprehend the trains of reasoning leading up to these various principles, and be able to apply them to the practical solution of problems. Great attention should be given to the working out of problems and exercises, and these ought to be carefully chosen, and should, in all cases, have a direct bearing upon the practice of engineering. This is a point of much importance. Very frequently the time of the student in mathematics is spent in the solution of problems, elegant no doubt in themselves, but of no practical value or page 40 interest whatsoever; while other problems, very nearly if not quite as well suited for the elucidation of the subject in hand, and of the greatest practical importance to the engineer, are totally neglected.

During this first year of study there should be no difficulty in mastering thoroughly algebra up to, but not including, the binomial theorem; plane trigonometry, as far as the solution of all the ordinary cases of right and oblique angled triangles; and the first six books of Euclid, together with exercises upon the various propositions. An agreeable relaxation from these somewhat severe studies may be found in spending a day, say, once a week in the practice of surveying.

The student might also spend a portion of his time in plotting the surveys, but I think it would be well for the present to make surveying and plotting secondary to algebra, Euclid, and trigonometry.

The first year's course satisfactorily completed, the student might be introduced into the office of an engineer in practice; here he should spend a portion, say about half, of his time in acquiring a practical knowledge of office routine, the other portion to be devoted to lectures upon the equilibrium and motion of rigid bodies and fluids. These subjects are of the utmost importance, and I do not hesitate to say that fully three-fourths of the errors and difficulties in which our practically educated engineers are so frequently involved are due to ignorance of these branches of inquiry. Here, as before, the student's ingenuity should be tested by an ample supply of problems and exercises, chosen as far as possible from actual engineering practice.

I am perfectly aware that the suggested division of the pupil's time between the office and the college would be looked upon with great disfavour by many engineers; but I am equally certain that, without some such arrangement, it would be extremely difficult for the student to obtain an adequate knowledge both of the theory and practice of engineering.

During the third year the greater part—say, three-fourths—of the student's time might be devoted to office work. He should now be competent to make original designs and working drawings for various minor engineering works, and also to perform the different operations of engineering field work, and in this way render himself of much value to his employer. The remainder of his time should be devoted to courses of lectures upon the strength of materials, the application of the page 41 principles of statics and kinetics to engineering structures and machines, and the principles to be observed in the designing of works. During the second and third years, lectures on chemistry and geology should be attended, as it is extremely desirable that every engineer should have a good general acquaintance with the principal facts of these sciences.

The study of higher algebra, of analytical geometry, and of differential and integral calculus, I do not regard as essential. Should the student, however, exhibit a taste for such subjects, let him by all means be encouraged to pursue them.

A thorough examination, extending over several days, and embracing all the subjects of the three years' course, would form an appropriate termination to the curriculum of lectures.

The engineer's education is not yet completed. It will be well for him now to spend from six to twelve months in the actual supervision of works in progress. He will thus gain much valuable practical experience, obtainable in no other way. He will be trained in judging of the quality of materials and workmanship, and will become acquainted with the management of contract work. At the close of a fourth year spent in this way a diploma or certificate of competency might be granted.

In order that the student may gain the greatest possible acquaintance with practice, it will not be sufficient for him merely to perform carefully such work as is specially committed to his charge. He ought also to take every opportunity of making himself acquainted with all designs, plans, schemes, and ideas in the office to which he is attached, and should master them completely, so as not only to know how any particular piece of work is to be executed, but also to comprehend the special reason or object of each detail. He should improve every opportunity of examining the practice of other engineers, and comparing it with that of his own chief; and by a careful attention to the literature of his profession, and especially such publications as The Transactions of the Institute of Civil Engineers, The Engineer, &c., should keep himself thoroughly conversant with all important professional questions of the day. With respect to this part of an engineer's education, Mr. Conybeare, who is a very high authority, speaks as follows:—"A thoroughly trained civil engineer's knowledge of practice, that is of examples of the application of scientific principles and formula; to all cases of civil engineering, is not confined to the comparatively limited series of works which have come under his own personal obser- page 42 various; for during his pupilage he is generally allowed access, under restrictions, to the far more extended series of engineering cases presented by the records of the office in which he is placed, comprising the working drawings and specifications of all works executed by his chief during his extended professional career, including those which had been used for the construction of some hundreds of miles of actually executed railway. And he should extend this series of examples by a careful study of the literature of his profession, by analysing carefully, note-book in hand, all the published drawings and descriptions of approved examples of engineering that he can obtain access to, entering in his notebook, in each case, the more essential particulars of the example, such as its dimensions, material, principle of construction; also, whether the end in view in each particular case appeared to have been accomplished more or less economically and efficiently than in other cases, where, with a similar diagnosis, a different treatment had been adopted; noting, as far as possible, which were the particular points in each example most worthy imitation, and which, on the other hand, were better treated in some other example. By this process he will bring himself to a nearer knowledge of the one best way of attaining the particular end in view; for in every possible problem in construction there must be some one specific way of solving it that is better than any other; and by thus possessing himself of all that his predecessors had obtained, he will at least get as near the best way as they did, if he cannot, on the stepping-stones of their experience, rise to higher things in his own practice.

"The practical study of the published accounts of engineering works should not be restricted to English examples, for there is much that is worthy of imitation in the practice both of French and of American engineers. The former have always been superior to ourselves as theorists; and the extension of railways and other engineering works in France has of late years given them a more extended field for the application of science to actual practice, which their superior mathematical education has enabled them to turn to the best account. Their more recent works are consequently deserving of the closest study, and their published memoirs are generally models of methodic and scientific description.

"And American engineering is very highly suggestive. Necessity is the mother of invention, and the peculiar circumstances of America necessitated the execution of ways of internal communication of immense length, the frequent page 43 bridging of mighty rivers, the formation of quays, jetties, and graving docks, for loading, unloading, and docking the largest vessels—in fact, of all the appliances that modern commerce requires—at a mere fraction of the cost which in Europe is considered indispensable for works intended to fulfil the same purposes, and which scarcely fulfil them any better."

Taking Mr. Conybeare's view of the case, it is plain that the greatest possible advantage is to be gained by travelling to foreign parts, and examining the peculiarities of engineering practice in different lands, and under various circumstances. This, however, will, on account of the great expense involved, be an unattainable luxury to many. Fortunately, photography offers a not altogether inadequate substitute, by supplying the student with faithful representations of important works in all parts of the world, and I would strongly recommend young engineers to purchase and study such photographs as they may meet with. By this means their ideas will be enlarged, and their practice rendered more intelligent.

To sum up, then—theory and practice are the two pillars upon which all sound engineering work must be based. A man understanding theory, but deficient in practice, may have good general ideas, but will utterly fail in putting them into execution. A man of experience, but destitute of theory, will be able to carry out ordinary work in a satisfactory manner, but, should he leave the beaten track and attempt anything original, will assuredly fall into the grossest blunders for lack of scientific training. Those who have been well instructed in both branches will become intelligent and scientific engineers, while all others will, to the extent to which they are defective, be professionally crippled.