A vessel was built on the Atlantic coast several years ago, and was engined by a scientific man. Every part was evidently planned in accordance with correct principles, so far as that particular part was concerned. The engine was triple expansion; the forward part of the shaft was made the correct size for the highpressure cylinder; the middle part was made the correct size for the intermediate pressure cylinder, with the high-pressure added, while the after part was made the correct size for the low-pressure cylinder, with the intermediate and high pressure added.

I had a talk with the designer of this strange-looking machine, and he was positive that the general practice of marine engine builders was all wrong in this particular, and on many other points.

But there are particular experiences that men acquire and that have a great effect in shaping their practice. For instance, in designing, say, a pump for high pressures, and large quantities, I might, under certain conditions of working, and with certain kinds of water, employ hard rubber valves in metal cases; while under other conditions of working and kind of water to be handled, I would prefer metal valves.

Yet I could not say in advance just what conditions would determine me to choose either way; for while the conditions might not be such as to give a promise of very great advantage to either the one kind or the other, something else, as for instance, what kind of valve could be most readily procured in the place where the pump was to be operated, might decide the question for

me.

I have said something about engineering being an exact science; this is true only in part. The laws that govern bodies in motion and at rest, the expansion of gases, the conservation of heat and energy, are all exact in their operation, and the same conditions will always produce the same results. But the engineer has to apply these laws and forces through materials in the structures and in the machines which he designs, which are ever varying in their qualities of strength and endurance, and which may behave satisfactorily at one time and fail utterly at another, when, to all appearances, the conditions are the same.

"Why," he asked, "should the crank-shaft be made of the same size throughout, when, if the engine is properly designed, the forward part transmits but one-third the work, the middle part two-thirds, and the after part the whole work of the engine?"

Here the want of experience resulted in a failure, because the designer thought that the general practice was the result of lack of knowledge. He could not foresee that his journals and crank pins, being all of different diameters and lengths, and consequently having different velocities, would wear unequally, and that the shaft could not be kept in line.

Two metal surfaces may work together, as a journal and bearing, with perfect results at one time, leading you to believe that you had reached the desired end of your search for a satisfactory

bearing; yet, when you duplicate it under apparently the same conditions, you can get nothing but disappointment, showing that your first work was very near failure, though you did not know it. This is why some experienced engineers never repeat what was thought by those not in their confidence to be a great

success.

Recently there were launched at the Union Iron Works, at San Francisco, two vessels from two sets of ways, parallel to each other. Now, two parallel lines are supposed to stretch out indefinitely, but never come together. Why did these two ships, launched on parallel lines, come together so suddenly, when their rudders were set to make them diverge ? We have not yet been able to find a reason for it.

Our experience is now against launching two ships at the same time from parallel ways; our experience forbids it being done in that way. Still, some one else might do such a thing and be successful, and thus acquire an experience totally different from ours, and never know how near he came to doing an unsafe thing.

This illustrates what I mean by saying that no man can impart his experience to another, as it is acquired for his own use solely. If we were to be guided by another's experience, progress would be at an end in certain directions.

Men have found that certain things could not be done, because they tried and failed; other men, searching for experience for themselves, will try to do these same things and do them successfully, and thus gather an experience that contradicts that of the others. And this process goes on continually.

What my experience tells me will fail, another's experience tells him will succeed, and yet my own experience must guide me, and not that of another. Experience is a thing of slow growth, for often the first impressions produced by our work have to be modified as certain tendencies on the part of the work develop.

This is especially true of moving mechanism. An engine or machine may make a fine start, and engineering experts may give good reports of it, so that its designer may feel justly proud of the result of his labors. But by and by certain tendencies begin to manifest themselves; workmen are employed nearly every night on it to keep it in condition to run in working hours; still the fatal tendencies keep developing until the machine is broken in constitution and must be abandoned.

This is the end of many a fair start, and alas, how many of the model engines and machines that get conspicuous illustration and description in engineering publications come to just such an end! On the other hand, machines that required careful nursing at the start have developed constitutional strength that enabled them to serve their day and generation with credit.

ABSTRACT OF THE MINUTES OF THE SOCIETY.

REGULAR MEETING, 2nd OF MARCH, 1898.

A regular meeting of the Society was held in its rooms, 1736-9, Monadnock Block, Chicago, on Wednesday evening the 2nd of March, 1898.

President Alfred Noble in the chair, Nelson L. Litten, Secretary. Forty-one members and guests present.

The minutes of the previous meeting were read and approved.

The Secretary reported for the Board of Direction, by announcing the election at its meeting on the 1st inst., of David Sloan, Francis B. Badt, Frederick Sargent, Henry J. Westover, Oscar Sanne, Wm. Kramer, J. G. Giaver, G. H. Hillebrand, David Macdonald, John H. Eustace and George T. Adams, as members. George C. Geraty and Emil K. May, as juniors.

Application for membership was received from Andrew H. Green and referred to the Membership Committee.

The report of the Committee appointed to prepare a memorial on the death of Edwin G. Nourse, was received and read by the Secretary. A motion was made and carried that the report be accepted and placed on the records of the Society and that copies duly prepared be sent to the family of the deceased.

The paper previously announced for the evening on "The Evolution of the American Type of Water Wheel," prepared by Mr. W. W. Tyler, was, in the absence of the writer, read by Mr. T. L. Condron. The paper described the varying stages of progress and detailed the difficulties which were met in the experiments that led up to the efficiency of the present type of wheel. After a short informal discussion the meeting adjourned.

SPECIAL MEETING.-16th MARCH, 1898.

A special (the 380th) meeting of the Society was held in its rooms in the Monadnock Block, Chicago, on Wednesday evening, the 16th of March, 1898. Second Vice-president A. V. Powell in the chair, and fifty-five members and guests present.

Mr. Dankmar Adler was presented and read his excellent paper on "Mechanical Plants in Large Buildings," touching upon methods of ventilation, lighting, heating, etc. The paper had the close attention of the audience, and was followed by an extended discussion of suggestion and explanation.

The secretary reported for the Board of Direction the election of Andrew H. Green to active membership; the receipt of applications for membership from Wm. A. Wallace and H. R. Safford.

Mr. Edward Hennessey was then introduced and read a paper on "Improved Portland Cement," prepared by Mr. John W. Dickinson, in which reference was made to the improvement in the preparation of raw materials, the necessity of careful grinding and burning to insure effective chemical combination of lime and silica, and advanced methods of mixing. An interesting discussion of the subject followed.

Adjourned.

ENTERTAINMENT-26th MARCH, 1898.

An illustrated lecture on Mexico was given by Mr. William J. Karner, C. E. at the Technical Club rooms, 230 So. Clark street, Saturday evening, March 26th, to the members of the society and their ladies; invitation was also extended to the members of the Technical Club and their ladies. A delightful

evening was spent by a considerable audience in viewing the wonderful scenery of that country and listening to the instructive and interesting descriptions.

At the conclusion a vote of thanks was heartily given the lecturer.

REGULAR MEETING--6th APRIL, 1898.

A regular (the 381st) meeting of the society was held in its rooms in the Monadnock Block on Wednesdsy evening the 6th of April, 1898. Second Vicepresident A. V. Powell in the chair, fifty members and guests present.

The minutes of the previous meeting were read and approved. The secretary read a letter from Prof. A. M. Feldman referring to the death of Sir Henry Bessemer and suggesting that the Western Society of Engineers be pioneers to stir up the prominent engineering societies of the United States in a movement to erect an enduring monument, in some shape, to perpetuate the memory of this great man. Mr. Liljencrantz moved that a committee of three members of the society be appointed to draft suitable resolutions and that Mr. Feldman be made chairman of the committee and authorized to select the other members; unanimously carried.

Gen. Wm. Sooy Smith was then presented, and read his paper on "Fireproof Construction and Prevention of Corrosion." At the conclusion of the reading the Chair stated that, as the second paper of the evening followed closely the line of the first paper, discussion would be withheld until Mr. Abbott finished reading his paper, unless objection was made. Objection not being offered Mr. Abbott proceeded with his paper entitled "Fire-proofing of Warehouses," presenting illustrations enlarged by the stereopticon. The pa pers were then discussed by Messrs Pond & Pond, Gen. Sooy Smith, Messrs C. L. Strobel, Q. L. Condron, H. P. Boardman, A. S. Coffin and Thos. T. Johnston. Mr. Condron moved that the subject be held open for discussion at the next regular meeting, May 4th; that in the meantime copies of the papers be furnished members. Mr. Liljencrantz offered as an amendment that copies be sent to architect societies, and that they be invited to take part in the discussion. Mr. Condron accepted the amendment and the motion was carried. Adjourned.

SPECIAL MEETING-20th APRIL, 1898.

64

A special (the 382d) meeting of the Western Society of Engineers was held on Wednesday evening, the 20th of April, 1898. President Alfred Noble in the chair. Fifty-six members and guests were present. The minutes of the previous meeting were read and approved. The Topical Discussion upon Electrical, Pneumatic and Mechanical Power Transmission in Manufacturing Establishments" was taken up. Prof. D. C. Jackson of the engineering department of the Wisconsin University opened the discussion by referring to the general availability, convenience and economy of electricity for power purposes. Mr. Eugene B. Clark, electrical engineer of the Illinois Steel Co., discussed the use and desirability of electric power in rolling mills, and cited the following as some of the uses to which it is applied in the Illinois Steel Company's plant.

1. Lighting-both arc and incandescent.

2. Series motor operations, as motors on traveling cranes, electric hoists and conveyors, changing and drawing machines, table rolls, transfer cars, etc. 3. Shunt Motors operated intermittently, driving lathes, shears, pumps, crushers, drills, etc.

4. Shunt Motors-operated continually.

5. Incidental uses.

Interest was added to the paper by a large number of stereopticon views of the features described.

Additional discussion upon the electrical division was had from Messrs. Brinckerhoff and Coster. The pneumatic section was then introduced by Mr.

James F. Lewis of the Rand Drill Co. Facts and figures were presented to show the efficiency of this power in every field of operation. It was claimed that very few situations could be cited where compressed air could not be used advantageously.

Numerous letters from railroad men were read emphasizing the efficiency and economy of using compressed air in connection with railroad workshops. The transfer of mail matter by the use of compressed air in Boston, New York and Philadelphia was also commented upon. Mr. Lewis referred to some experiments with "Liquid Air" which he witnessed in New York City. Mr. C. W. Melcher, of the Ingersoll-Sergeant Drill Co., next presented a paper with a considerable number of views, adding further testimony to the confidence compressed air is establishing as to its fitness in various works. Mr. H. J. Westover, of Sargeant & Lundy, taking up the mechanical question, gave a number of figures of practical tests of the transmission of power direct to machines through several belts, etc. Mr. Robert Ardell, of the Link Belt Machinery Co., presented the American feature of "Manilla Rope Transmission," illustrating his remarks with twelve lantern illustrations.

Mr. Thos. T. Johnston, assistant chief engineer of the Chicago drainage canal, suggested in a brief way the transmission of power by water-the advance recently made in the design and manufacture of water motors. A general discussion followed, and the interest prolonged the meeting to a late hour.

It was announced that the society had leased additional space increasing the size of their rooms about fifty per cent, as the present quarters have become too small to meet the demands and increasing interest in the society.

The secretary reported the election of Mr. Wm. A. Wallace, assistant engineer C. I. & L. Ry. Co., as active member, and Mr. H. R. Safford of the I. C R. R. Co. as junior. Adjourned.

NELSON L. LITTEN,

Secretary.