With the modern tendency toward specialization, the natural outgrowth of necessity, there is no inherent reason why the bones of a building should not be devised by one man and its fleshly clothing by another, so long as they understand one another, and are in ideal agreement, but there is in general all too little understanding, and a confusion of ideas and aims. To the average structural engineer the architectural designer is a mere milliner in stone, informed in those prevailing architectural fashions of which he himself knows little and cares less. Preoccupied as he is with the building's strength, safety, economy; solving new and staggeringly difficult problems with address and daring, he has scant sympathy with such inconsequent matters as the stylistic purity of a façade, or the profile of a moulding. To the designer, on the other hand, the engineer appears in the light of a subordinate to be used for the promotion of his own ends, or an evil to be endured as an interference with those ends. As a result of this lack of sympathy and co-ordination, success crowns only those efforts in which, on the one hand, the stylist has been completely subordinated to engineering necessity, as in the case of the East River bridges, where the architect was called upon only to add a final grace to the strictly structural towers; or on the other hand, in which the structure is of the old-fashioned masonry sort, and faced with a familiar problem the architect has found it easy to be frank; as in the case of the Manhattan Storage Warehouse, on 42nd Street, New York, or in the Bryant Park façade on the New York Library. The Woolworth building is a notable example of the complete co-ordination between the structural framework and its envelope, and falls short of ideal success only in the employment of an archaic and alien ornamental language, used, however, let it be said, with a fine understanding of the function of ornament.