Did you ever have a boss who was out to get you? That's what bridge designer Charles Ellis thought about his boss on the Golden Gate Bridge project, Joseph Strauss. Relations between the two men went sour over time, and ended with Ellis' summary dismissal from the project in late 1931.
Ellis couldn't stop thinking about the bridge, though, and subsequently spent months, without pay, calculating and recalculating the design.
By mid-1932, Ellis was lobbying to present his new calculations. He hoped to demonstrate that the bridge, as designed, would be unsafe. Ellis wrote a letter to a journalist at the San Francisco Chronicle, presenting his side of the story. Do you think Ellis was over-careful? Or was Strauss heedless in his rush to start building the bridge? Read this letter and make up your mind.
Ellis' Letter to George Cameron of the San Francisco Chronicle (January 4, 1933)
638 Garrett Place
January 4, 1933
Mr. George T. Cameron
San Francisco Chronicle
San Francisco, Calif.
Dear Mr. Cameron,
In accordance with your suggestion made at our last meeting I send you my address for you files; I include also some historical data for your information, answer a few questions and finally add some suggestions for your consideration. I fear the letter will be too long for such a busy man to read but I shall avoid technicalities as much as possible in the hope that you will have on record for reference a true picture of the situation.
Fist I will recite a few events arrayed chronologically.
March 11, 1930
Preliminary test borings completed. I left San Francisco for Chicago and started the preliminary design and estimate. I had many times tried to convince Mr. Strauss that a year would be necessary to do this work properly.
Plate girder, simple truss, arch and cantilever spans are very much alike in that they all perform their duties as a beam in resisting bending moments and shears. A suspension span is in a class by itself since it acts like a clothes line instead of a beam. Hence it is at once obvious that an engineer may be thoroughly familiar with all other types of bridges and yet be a novice in suspension span theory and design.
Such was the situation in our office. I could not turn over the computations to any one else but had to make them myself, and at the same time initiate one of our men, Mr. Clarahan, a former student of mine, into the fundamental theory. Mr. Strauss, however, insisted that the work must and could be done in three or four months, inasmuch as he would write the report in San Francisco while I was making the design and estimate in Chicago.
There was a large bascule bridge job going through the office at this time in charge of Mr. Paine on which a bonus was to be paid if completed on a given date and because of this, it was with much difficulty that I was able to arrange for the release of a few men to help me. By working twelve to fourteen hours a day I personally made all the computations and the entire design and with a few men at my command -- at most six or eight at any one time -- the plans were sufficiently laid out so that on
June 12, 1930
A meeting with the three consultants was held in Chicago to review the work. Mr. Strauss was also here. Three sessions were held on each of two days attended by the consultants and myself. During all these sessions except the last one when his report was discussed Mr. Strauss, the chief engineer, was not in the room once to sit down or take any part in the discussions. Subsequent to this meeting the plans were finished, tracings made and on
I arrived in San Francisco with the preliminary plans completed. Mr. Strauss had meanwhile written his report in San Francisco so that it can be correctly stated that he knew as little about my plans as I knew about his report.
Some of the Directors who reviewed his report were not satisfied with it. I understand that the Directors cut out much of it and turned the remainder over to Mr. Taylor, the traffic engineer, to rewrite for publication. Several of the Directors and the General Manager asked me confidentially for my opinion of the report and my reply was that, since I was in Mr. Strauss' employ, I must decline to comment. Mr. Strauss, however, arrived at the erroneous conclusion that the dissatisfaction on the part of the Directors was traceable to me.
It was at this time that I first felt Mr. Strauss' displeasure. For years it had been thoroughly understood that I was to have charge of this work, and that at the proper time we would transfer all the work to San Francisco where I would be located as Resident Engineer.
It was also understood that when the preliminary plans were delivered, I should remain in San Francisco and give technical advice during the bond campaign, but when he realized that the Directors were coming to me for information and advice he instructed me to return to Chicago at once.
November 4, 1930
Bonds voted. Mr. Strauss immediately sent for Mr. Paine who up to this time had had absolutely no connection whatever with the work or any other work of the suspension type. He was a former student of mine and was brought into the Strauss organization several years ago by me. He was in San Francisco about two weeks. Two days before his return to the office I received a letter from Mr. Strauss which in effect took the work out of my hands and placed it in charge of Paine with no reasons or explanations whatever given for such a drastic action.
The only portion left in my charge related to the computations and specifications. This arrangement made an almost impossible situation since the computations, design, plans and specifications were all so closely interwoven that to separate them was simply inviting complications.
Probably the only reason the computations were left in my hands was because, with the exception of Clarahan who was just getting his initiation into this sort of work, I was the only man in the organization who had even the slightest conception of what the computations were all about.
When these arbitrary instructions with no explanations were received my first impulse was to resign. It happened that one of the consultants passing through Chicago the following day came into the office and I informed him of the action. His advice was not to resign but to carry on for the good of the project, irrespective of the circumstances. I soon learned what all the consultants thought of the action and concluded to continue although it was not an easy or pleasant task to do so.
The work in hand at this time was the preparation of the specifications and the elaboration of the plans so that lump sum bids instead of unit price bids could be taken, to comply with the promise made by the Directors to the electorate during the bond campaign. In addition to this, Mr. Strauss had some new ideas which he wanted to incorporate in the design of two approaches adjacent to the suspension span, and he decided that, since he had organized a resident staff in San Francisco with a Mr. Pratt in charge, all work on the approaches and viaducts could be done in the San Francisco office with the understanding that it be sent to Chicago for checking and approval. This arrangement caused no end of trouble, since neither Mr. Pratt nor the men under him proved competent to do the work and most of it was done over once or twice. The above relates to the two Presidio viaducts some distance from the bridge.
January 17, 1931
A meeting of the consultants was held in San Francisco which Mr. Paine and I attended. On our arrival I discovered to my astonishment that Mr. Strauss was actually substituting a one thousand foot suspension span in place of the ordinary steel viaduct as shown in the preliminary plans for the Marin approach, and a young chap in the office was attempting to design it. I took the chance of further arousing Mr. Strauss' antagonism by attempting to explain the folly of a design so unnecessary and expensive. It was only with much pleading that I kept him from submitting this design to the consultants for their consideration.
Following this meeting I returned to Chicago and gave my attention to the specifications.
March 18, 1931
Meeting of Consulting board in Chicago. When Mr. Strauss came on to this meeting he brought with him copies of the specifications for the whole job which he, with Pratt's assistance, had prepared in San Francisco, using in part the rough drafts which I had been sending him. I had not heretofore known that he was giving any attention to this work. He stated, however, that as he wished these to be "the best specifications yet written and to serve as a sort of model for future engineers to follow" he had taken a hand in the work himself, and asked me to read them, calling his attention to any errors before he submitted them to the board.
I found them in such shape that nothing could be done with them. He insisted that they could be corrected as written and Paine agreed with him. They were finally submitted to the board as prepared, and that was the last that was ever seen or heard of them.
I completed my drafts. They were approved with only slight revisions by the consultants and appear in 8 columns as the official specifications. This and several other instances of a similar nature where it was necessary to oppose Mr. Strauss in order to serve his best interests helped to widen the breach.
June 17, 1931
In San Francisco with the consultants at opening of bids. It was at this meeting that one of the consultants suggested to Mr. Strauss that I should be located in San Francisco in charge of this work. This was not received with very good grace and the three consultants discussed the matter with the general manager, after which the manager and the consultants took it up with Mr. Strauss who refused to consider the suggestion. I knew nothing of these conferences until one of the consultants told me about them afterwards.
I asked Mr. Strauss at this time to tell me frankly what was the matter. His reply was an attempt to assure me that nothing was the matter, that I was very valuable to him and that I had no cause to worry about my connection with him or with the Golden Gate project.
On my return to Chicago I set to work on the refinement and elaboration of the computations which had already been too long delayed while I was working on the specifications. I began with the stiffening truss computations. While I was working on these Mr. Strauss wrote directly to Clarahan instructing him to make a set of tower computations independent of my suggestions, instructions or directions.
Mr. Clarahan started out independently but it was not long before he came to me for help. I told him that we had best maintain independent work according to instructions.
The so-called slope-deflection method was used. This is a well established but not widely known method. The general theory is not new, but its application to wind stresses in rigid frames without diagonal bracing, as in office buildings, was developed to a high degree by Professor Wilson, one of my assistants while I was a Professor in charge of Bridge and Structural Engineering at the University of Illinois. I think, therefore, it may be assumed without error that I am thoroughly familiar with the general theory and its application. This was, to the best of my knowledge, Mr. Clarahan's first introduction to a problem of this nature, and I was not surprised that he had difficulty. He spent about three months on his computations and when they were finished I saw that his results could not possibly be correct.
It was late October or early November before I was able to begin with the towers. My study had not progressed far when I realized that a number of new mathematical expressions would have to be developed before the general theory could be made applicable. And these took a lot of time and much concentrated thought. It was about this time that Mr. Strauss was urging me to start on my vacation. I wrote him at great length telling him why Clarahan's work was wrong, and that there was no thought in my mind of a vacation until the towers were completed. His reply was a wire to start my two weeks vacation December 5. Three days before the end of the two weeks period he wrote a letter criticizing my conduct of the work, and stated very clearly that "the structure was nothing unusual, and did not require all the time, study and expense which I thought necessary for it," and closed by instructing me to turn over all papers to Clarahan and take an indefinite vacation without pay.
Early in the year I wrote my discussion of Mr. Moisseiff's paper on "Lateral Forces in Suspension Spans" appearing in the Proceedings of A. S. C. E., after which I found myself with nothing in particular to do and with the thought of the condition of the towers constantly in my mind I was certain that when the questions came to an issue, as it surely must, the responsibility for any errors or delay on account of them would be placed at my door. Furthermore, here were several interesting problems that required a solution. Consequently I started a study of the towers, unhampered by any feelings of haste, and with ample opportunity to give them the study they deserved.
There were two problems in particular which, to me at least seemed at first insoluble with our present knowledge in the theory of structures, and which do not appear on the surface of the main problem. They arose at critical points and solutions were necessary. After several weeks of intensive study they yielded to a solution in the discovery of what might be called a new principle -- if not a new principle -- certainly a new method in the adaption of well known principles to suit the emergency.
Please remember that I was thoroughly acquainted with the towers when I started this work, and with previous studies at my command I anticipated that a month would be ample time for a complete review. I now know how erroneous was my estimate for I worked on the problem continually over ten hours a day, seven days a week, for nearly five months and the work was completed in October.
I believe I am now in a position to speak with some assurance and authority concerning the design, and I have set down a few points that I know to be facts.
1. No change has been made in the general dimensions or the configuration of either the tower legs or the bracing.
2. It was my suggestion that the base be redesigned as an integral part of the tower. This was done, although I had no part in the design nor was I consulted about it. I am now certain that this base should be redesigned along scientific lines to meet the purposes for which it was intended.
3. Changes should be made in all tower sections except the two sections A and A1 at the top.
4. The entire bracing system, both struts and diagonals require a complete new design, not only in the areas of the members but in their general make-up as well.
5. Any engineer however familiar he might be with the general theory of expressing moments in terms of angular deflections would simply be making a guess if he tried to estimate how long it would take him to go through with this work, which I have now completed. It is not a problem upon which a half dozen men can be set at work, -- it is practically a one man job.
6. Any engineer, however familiar he may be with the general theory will, before he goes far with the problem, have to learn how to do certain things for there is considerable original work to be done. Incidentally, there are 113 equations containing 39 unknown quantities to be solved in checking up the design after it has been completed.
7. If any engineer fully qualified should attempt a comprehensive and detailed investigation of the towers, which the work I have now done proves conclusively to be very necessary, it would develop that the towers would not be ready for the fabricator to start work or even order his material for at least four months. Such a person does not exist in the Strauss organization, or did not when I was asked to leave. Clarahan is the only man who knows anything about a problem of this sort and his computations are clearly in error.
These seven statements were made known to the consultants early in October.
It may be well at this time to answer several questions which no doubt have come to your mind.
(1) Why should revisions in my original design be necessary?
Due to Mr. Strauss' insistence the towers have no diagonal bracing above the floor, each tower is therefore what is known as a statistically indeterminate structure. The moments, shears and resulting stresses cannot be determined by the principles of statics alone, and additional data must be obtained from the behavior of the structure under stress, by taking into account the distortion of the members and the corresponding deflections of the various joints. In the use of these data one meets with unknown quantities which should be determined by setting up and solving as many independent simultaneous equations as there are known quantities.
The amount of work involved is greatly reduced if the number of unknown quantities is kept at a minimum; and this may be accomplished by making certain assumptions as to the behaviour of the structure, or perhaps by assuming equality between a pair of unknowns that appear to be nearly equal or by assuming that certain unknowns have so little influence on the structure that they may be neglected altogether. Such a procedure can be justified in a preliminary study when speed is urged (as it certainly was in this case) but always at the expense of accuracy. The computations for the preliminary design and estimate were of this latter character. Precision was not required, since the preliminary work was only for the purpose of arriving at a reasonably approximate estimate of the cost.
I concluded that in the preliminary computations all but 13 unknowns could be assumed and the design was made on this basis.
In an ordinary structure such as a competent engineer has designed many times, his knowledge, judgment and experience will enable him to make assumptions with sufficient accuracy so that the errors, if any, will be negligible; but in a structure of this size, so novel and extraordinary, any assumptions are attended by considerable sacrifice of accuracy as I had ample opportunity to learn in the present case. I realized that the final design for construction purposes was an entirely different matter, also that this structure would attract a great deal of attention, and would be the subject of many technical papers and discussions thereon. These were the facts that gave me worry after I had decided that my services were no longer required.
Having these facts in my mind I decided when I began my study last April to eliminate all assumptions, that could possibly have any influence on the structure, and to solve for each unknown that would have the slightest importance. I set up algebraic expressions for 38 unknowns as against 13 in the preliminary work, which means that 25 assumptions appearing in the preliminary design were eliminated in my final computations. The correct result instead of an assumed value which was only approximate (and in some instances hardly that) in 25 instances can easily account for considerable differences between the preliminary and the final designs. In other words the preliminary design is superficial and approximate: the final design is thorough and correct.
(2) How many assumptions has Clarahan used in his computations?
The independent computations which he had made before I left the office are fundamentally and radically wrong to start with. There is and can be no question about that. I could prove this fact to any layman to his satisfaction in three minutes. It may be assumed, however, that my letter to Mr. Strauss, explaining the nature of Clarahan's mistakes, found its way back to Clarahan and he could benefit thereby.
Be that as it may, Mr. Strauss has submitted Clarahan's computations to Mr. Moisseiff for checking, and the question that at once arises in my mind relates to the thoroughness of Clarahan's solution. In other words, in how many instances has he been content to make assumptions as to values instead of introducing unknowns into the problem and solving for correct values? Unless Clarahan has gone into the problem with sufficient thoroughness by eliminating all assumptions (which I very much doubt not only because of Mr. Strauss' general policy of haste) the checking of his work will be of no avail, for although the work may be arithmetically correct, the final results will contain all errors made in the assumptions.
Some importance should be attached to the arrangement made for the checking. The Consulting Board desired this work to be done by Moisseiff. Mr. Strauss could raise no objection to this but he could quite properly maintain and insist that the District should bear the expense. It is extremely interesting to note that Mr. Strauss offered to bear the expense himself, and the result is that the report is to be submitted to Mr. Strauss before being submitted to the District.
(3) Is Clarahan's design the most economical?
Some one has said that an engineer is a man who can design a structure for $100,000, that anybody could design for $500,000.
Several designs might be developed with slight variations, all of which might be equally adequate yet one of them would undoubtedly be more economical than the others; and it should be remembered that in a structure of this size reasonably small variations in design may represent differences in cost of one hundred thousand dollars or even twice the sum.
I have avoided technical terms as much as possible in the hope that I have given you sufficient light on the subject to conclude that the five months independent work I have done on these towers is worthy of at least a hearing. Three consultants instead of one were chosen for no other reason than that three minds are less likely to err than one. Following the same principle, cannot the District justly afford to take whatever advantage there may be in the work of the man who initiated the general makeup, dimensions and design of the structure and who has spent many more hours of study on them all others combined?
All this work has been done on my own time and at my own expense. I have done it not only because I was intense interested in the problem from a strictly scientific and academic standpoint, but also because I knew that it would save the District at least four months time.
I have worked three years and more on this job; I personally made all the computations and design and wrote the specifications. Naturally it is very close to my heart, and I cannot face the possibility of having the work start off on a design which my five months intensive study has convinced me needs revisions.
I would greatly appreciate the opportunity to present my computations and design for the consideration of the District. Would it not be the advantage of the entire project if a meeting could be arranged for a frank discussion and comparison of these two final designs? Just how this can be best accomplished is of course for the District to decide. I cannot speak for the consultants but I feel sure that some if not all would heartily welcome the idea.
What seems to be most important at the present time is to find someone who will bring this question to an issue. May I suggest that you discuss the contents of this letter with Mssrs. Filmer, Kaesling and Derleth and let me know the conclusions reached.
In closing I wish to express my appreciation of this courtesy and consideration which you showed me while I was in San Francisco.
Yours very truly,
P.S. Since I am sending this Air Mail, I shall be glad to learn that it has reached you safely.
My American Experience
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