Our Four Big Bridges
From ARCHITECTURAL RECORD, March 1909
One of the reflections which force themselves upon the New Yorker who has occasion to investigate for himself, and in an amateur way, the way of the lover of beauty and fitness, the two biggest and costliest of the bridges at present under construction by this municipality of Greater New York, is a discouraging reflection. How grievous is the injustice that is done us by our press.
In the matter of public works the press seems to be interested only in the incidental scandals which may arise out of them. All, or almost all, columns are joyously opened to scandals about bridges, as about other costly and important public works. If they turn out to be, or are even plausibly alleged to be, inadequately designed, that is well. If they can plausibly be alleged to be "gigantic jobs," that is immensely better.
But if they are simply uncommonly and creditably well done, so as to be among the glories of the city and the country, you will be long in finding out that uninteresting fact from the ordinary newspapers. One who has of his own motion investigated the construction of the newer bridges across the East River, for example, feels himself to have a grievance when he finds a wealth of interest in them, and a just source of local pride, of which his newspaper had given hint no hint whatever. Not only has it not told him "the half." It has had nothing at all to say about the matter. Perhaps he ought not repine at having so nearly a virgin field, and ought to he grateful even for his grievance. But what a social symptom the grievance nevertheless is!
In truth, one who visits the Blackwell's Island and the Manhattan Bridges finds great matter for wonder and admiration at the enormous artistic advance they show upon the older bridges across the East River. This is very especially the case with the present writer, who may be pardoned for recalling that he made, a quarter of a century ago, a critical examination of the then new and now old East River Bridge, for Harper's Weekly, in which the results published, were so far as he knew or knows the first attempt that was made in this country at an aesthetic consideration of an important engineering work.
It was an endeavor to test an engineering construction by architectural principles to judge it, as Ruskin has it, "by those larger laws in the sense and scope of which all men are builders, whom every hour sees laying the stubble or the stone." Specifically, what one demands in such a work is "the adaptation of form to function," or, in other words, the following out of the indications inherent in the mechanical dispositions and devices, instead of the imposition upon these of ideal, or of conventional forms. In this mode of procedure, as an eminent American architect has described it, you do not so much design your edifice as you "watch it grow."
And, in the old East River Bridge, it is interesting and instructive to note that the successes are all won by letting the structure "do itself," so to speak, the failures all incurred by forcing it to do something else. (Fig. 1.) Even to-day, much as with our present lights it might have been still further lightened and skeletonized, there is no finer thing in its kind to be seen than the gossamer structure of the metal, the airy fabric that swings between the towers.
The spider's touch, how exquisitely fine!
Feels in each thread and lives along the line.
The stiffening truss itself of the roadway asserts itself as a stiffening truss without asserting itself unduly. And nothing could be happier than the relation between the "camber" of the roadway, with the enormous radius of its slowly climbing curve, and the swifter swoop of the catenary curve of the suspensory structure. These things, it is plain, are simply submissions to the dictates of mechanical laws and of the actual conditions of the erection, the requirement in the interest of navigation of a minimum height above the river at the centre, the requirement in the interest of accessibility and accommodation of the situation of the terminals.
The resultant relation is artistically perfect. The height of the towers, again, is fixed by the length of the span and the imposed necessity of keeping the bottom of the catenary at a fixed height above the river; the bulk of the towers, given the necessary massiveness of their masonry, by the load they have to sustain and the necessity of maintaining them against any wind that can blow. These things, again, are as perfectly satisfactory to the eye as we must assume that they are responsive to the mechanical requirements. But in the detail of them we cannot help seeing that caprice has been allowed to play its part; that. the form is by no means "inevitable;" is, in fact, contradictory of the function. The function of the towers, for example, is merely that of cable-holders. Nobody would ever guess it to look at them.
The curve of the cables continues over the saddles, which are shaped accordingly, and it is a necessary condition of the operation that the cables should move freely in the saddles, thus providing for expansion and contraction under stress of the weather, allowing the "play," which the late Abram S. Hewitt, in his admirable address at the inauguration of the great work, pointed out was so essential to the working of so huge a structure of expansive and contractile metal. Quite manifestly the cable-holders should have been so modelled as to express this function, modelled in their turn into "saddle-backed" roofs. In fact, they are so modelled, in deference to antique monuments which had nothing whatever to do with the case, as quite to conceal this primary function as though it were something to be ashamed of, instead of something to be exhibited and emphasized.
The half catenary seems to be imbedded in the tower on each side, and there to cease and determine, instead of being a~ necessary link in a continuous and mobile chain. One more or less vaguely feels, in the presence of the actual work, how "irrelevant, incompetent and impertinent" to the purpose of the structure is this actual tower, with its flat top, of which the flatness is emphasized by the projecting conventional cornice copied from monumental structures of far different conditions and purposes. But one perceives it in a clear and even in a ludicrous light when he examines the section (Fig. 2) in which the course of the cables is shown, and the form of the enveloping structure, which has nothing whatever to do with the case. The new architecture of spun metal discredits and shames the outworn and out-of-place survivals of the older architecture in massive masonry. One is a "graphic linear demonstration" of the mechanical facts of the case, the other a crude approximation to an expression of them where it is not a senseless departure from them.
The anchorages of the old bridge share the defects of the towers. The savage who essays a suspension bridge across a gulch in the Andes must drive down stakes or heap up stones or tie his grass-woven cable to a tree to hold it in place while his crazy structure is swinging. To hold the cable-end firmly is equally the function of the anchorage of that wonder of mechanical refinement, the modern suspension bridge in metal. But there is no mechanical refinement about the design of these anchorages. They are simply huge cubes of masonry into which the cable disappears, not by which it is visibly clutched and held. Most spectators of the Brooklyn Bridge probably fail to distinguish the anchorage, which is an integral part of the structure, from the approaches of which the purpose is simply to give access to it.
In these approaches, and in these alone, of the old bridge, architectural counsel was invoked by the designer, although unhappily the design of the sheds at either end was confided to the untutored and unassisted engineer, with grievous results, the most grievous of which is, perhaps, that the great structure itself is rendered quite invisible from either end, and that you have to go out upon the river or scale a skyscraper to get a look at it. Upon the whole, the approaches vindicate the taking of architectural counsel.
But there is one detail of them which in its results is more than a detail, and that is the employment, in all the arches of the approach, of the form called "Florentine," that is, circular within and pointed without, and hence deepest at the crown and shallowest at the haunches. As was remarked in the study to which reference has been made, this disposition is "the reverse of that which would have been dictated by mechanical considerations alone," and whoever discards mechanical considerations in a great work of utility like this assumes a grave responsibility.
It is true that the form enhances the perspective effect and the apparent length of a diminishing arcade, such as the arcade of the approach is, looking landward, or from the larger to the smaller arches. But it correspondingly shortens the apparent length and diminishes the perspective effect of the enlarging arcade in the view toward the river, which is the more important view. All this, however, does not prevent the Manhattan approach to the old bridge from being tremendously impressive. The great openings that span the streets (Fig. 3) have the advantage of giving, what one finds so rarely in our rectangular town, random and accidental and picturesque points of view, and some sense of wonder and expectation and mystery, as of
an arch wherethrough
Gleams that untraveled world.
And one does not in the least regret, contrariwise one welcomes, the effect of the humble brick fronts, of red and yellow, which have been put in as filling to the intermediate arches to utilize them as practical warehouses and places of storage. (Fig. 4.) The manner in which these interpolated fronts have weathered and mildewed, within only a quarter of a century, makes them as grateful objects as a hunter after the picturesque can find in the street architecture of New York, gives New York, indeed, so far as their effect goes, that air of an "Eternal City" which it hardly anywhere else conveys, excepting in the rough and smoke-stained masonry and brickwork of the old Harlem Tunnel, which such a spectator regrets to see being supplanted by frameworks of metal.
The one lamentable addition to the approaches of the bridge since its erection is the slim metallic supports of the widened roadway, which are not only perfectly unimpressive and unattractive in themselves, but which tend to vulgarize and destroy the effect of the massive masonry before which they are placed, and without any real utilitarian excuse, since it is quite plain that the widened roadway could equally have been carried upon projecting brackets as upon vertical stilts, and would in that case have even enhanced the effect which it now disfigures. But, when all is said against it that can fairly be said, it will remain true that the old bridge is a great credit to its builders, a valuable artistic possession of the city which it serves with a service so far transcending the expectations of its projectors.
The Williamsburg Bridge, not far from midway, in point of time, between the old East River Bridge and these two later, of which one is hardly finished and the other in an early stage of its construction, doubtless shows a scientific advance upon its predecessor, so active and fruitful in the history of engineering was the decade or more that intervened between the completion of Roebling's work and the beginning of this.
But by common consent there was no corresponding artistic advance. Quite the contrary. (Fig. 5.) In fact, the ugliness of the Williamsburg has been the means of an increased appreciation of the beauty of the East River. One does not imagine what stream the later could suitably span, unless, indeed, modern progress should supersede Charon's ferry by a bridge for the traffic of the Styx, in which case passengers outward bound might perhaps feel that their conveyance was appropriate to their destination, In spite of the proverbial prohibition against speaking ill of the bridge which has carried you safely over, the Williamsburg, as a work of art, has no friends. The most conspicuous of the differences between the two is that the towers are in the older of masonry and in the later of metal. Presumably the difference was primarily economical.
One can hardly imagine an engineer preferring a tower of attenuated metal to one of massive stonework if he were free to choose. And, indeed, it might well be wished that some architect worthy of the work had had the opportunity to show what grandly monumental objects stone towers as huge as those of the old bridge might be made by modelling them with reference to their functions, and not at all with reference to inapplicable precedents, antique or mediaeval. But, even if one admits that masonry is the more eligible material, one is not forced to admit that nothing much better can be done with metal than was done with it in the towers of the Williamsburg.
The Tour Eiffel already stood to show what grace and inspiration could be imparted to a metallic tower by the right designer. And Mr. Lindenthal's unexecuted project for a suspension bridge across the North River was also extant (was it not?), reproducing with great effectiveness, and on a scale not so very much smaller, the continuous concave outward curve from summit to base of the Parisian monument in metal. The chief ungainliness of the towers of the Williamsburg is imparted by the abrupt change of direction of their bounding lines, from a very pronounced "batter" above the roadway to a very nearly vertical line beneath it, an unhappy change that gives the towers an uncouth and bandy-legged aspect which no cleverness of detail could redeem.
The most effective aspect of these towers is the view from underneath (Fig. 6), where this deviation of line is not noticeable, and where the rowers, with the arch between them, form a really impressive example of the skeletonized architecture of metal, in which attenuation and articulation become the elements of impressiveness, as opposed to the massiveness and solidity of aspect proper to masonry. Another deviation of line entails almost as disastrous artistic results as the change of direction in the outline of the towers. Instead of the continuous slope of the East River Bridge from approach to centre and down again, it is here only the roadway between the towers which shows a curve, abruptly changed to a straight line outside them.
And a third deviation of the same kind puts it quite out of the question that the structure can ever compete as a thing of beauty with the older bridge. This is again an abrupt change of line, the substitution of the straight backstay for the half catenary as the connection of the cables with their anchorages. Scientifically accurate and competent it may be, but it is architecturally most injurious. An eminent engineer to whom I was deploring it observed that I probably did not understand the real motive of the substitution–"It saves a heap of computations." Which is all very well; but a man who is not willing to take trouble about the appearance of his work must not call himself an artist.
These three unnecessary and unexplained solutions of continuity would of themselves be fatal to the artistic success of the work which they disfigured. But there is still another drawback almost equally injurious, and in this case injurious to the aspect of the suspensory structure itself, of the bridge between the towers which in almost all suspension bridges cannot help being attractive. That is the enormous depth and the insistent conspicuousness of the stiffening truss of the roadway. In the old bridge this member simply suffices to give needed emphasis to the line of the roadway, while yet it is obviously subordinate and accessory to the suspensory structure, which is "the thing."
In the Williamsburg it becomes so insistent that it almost seems a question which of the constructions is auxiliary to the other, whether a huge trussed girder is only assisting a suspension bridge or is only assist~d by it to the extent of a suspensory arrangement to relieve the strain at the centre. No accessories, it is evident, could make an admirable or even a presentable work of art out of a project so bedevilled in the primary conception.
To invoke an architect to improve its appearance after it is done were a futile and ungrateful requisition. As Polonius has it–"Beautified is a vile phrase." It is particularly a vile phrase in bridge-designing. Doubtless it were impossible that the approaches in metal to this bridge could have the impressiveness of the approaches in masonry which we have been admiring.
But it may be noted that, though a plate-girder offers a less interesting surface than a bonded stone wall, the projection of the roadway beyond the structure of the approaches themselves is far better managed here (Fig. 7), where. the projections of the roadway are carried on brackets, than in the East River Bridge, where they are supported by vertical posts from the ground. More "evidences of design" in the brackets would make the arrangement not only presentable, but attractive.
One must also praise the arrangement by which the structures of the terminal are sunk so far out of sight as to preserve the endwise view which in the old bridge is effaced, and which would be so much more valuable there than here, if one could only see it. (Fig. 8.) Moreover, these unobtrusive structures are in themselves admirably designed and appropriately detailed. (Fig. 9.)