The approaches themselves are greatly impressive, as indeed the towers are also, by magnitude and massiveness. The street bridges are uniformly imposing by size and span, and especially attractive also by reason of the fact that through them we get what is to be got nowhere else in our rectangular city, glimpses and “bits” of buildings. The most successful of them all, and the most successful feature architecturally of all the masonry of the bridge, is the simple, massive, and low bridge of two arches which spans North William Street, in New York. The arcades between the streets are imposing by number and repetition as well as by massiveness, and by the Roman durability which marks all the work. They suffer, however, from two causes. The coping, the arches, and the piers, which are the emphatic parts of structure, are lighter in color than the unemphasized and rock-faced fields of the wall, and this is always a misfortune when it is not an error. The arches are of the form called “Florentine”--that is to say, round within and pointed without. The deepest voussoirs are thus those at the crown of the arch. This is the reverse of the disposition which would be dictated by mechanical considerations alone. Architecturally it has the drawback of interrupting at every arch the successive and diminishing wheelings which make a long arcade of great openings so impressive in a perspective view. The form seems to have been chosen on account of the facility it afforded, by lengthening the upper voussoirs, to conform the ridge line of the arches to the slope of the roadway, while keeping the springing line horizontal. This gradual diminution of the arches shoreward enhances the apparent length of the approach looking in that direction, but correspondingly shortens it looking towards the bridge; and it seems, upon the whole, that it would have been better to carry the arches through level, without attempting to dissemble the difference between their line and that of the roadway. There are some shabby and flimsy details of iron work, which mar the monumental effect of the great roadway itself, while the design of the iron stations at either end is grossly illiterate, and discreditable to the great work. Imitations in cast iron of stone capitals surmount and emphatically contradict posts profusely studded with bolt-heads; and other solecisms, alike against constructional reason and architectural tradition, are rife in these unfortunate edifices, which do what they can to vulgarize the great structure to which they give access.