32 



vertical lift span and about 4,270 feet of approaches, or a total length of 6,306 feet. 

 The steel spans are supported on concrete piers and the approaches on reinforced 

 concrete piles. The entire structure cost about $2,000,000. 



Projects for other large bridges across the bay and the Golden Gate are actively 

 promoted but are not yet sufficiently crystallized to warrant their discussion here. The 

 city of Oakland has voted $9,000,000 to begin the development by that municipality 

 of adequate commercial wharf and terminal facilities on its extensive waterfront. No 

 construction details have yet been given out, however. 



In conclusion, the gradual adoption of protected substructure materials has been 

 accompanied by the establishment of modern wharf facilities throughout the Bay. 

 The Port of San Francisco has been developed to a point where its facilities rank with 



Fig. 16. Carquincz Bridge during construction. Lalilurnia and Hawaiian Sugar Co. plant (location 

 of test station C) is behind approach at right side. 



(Pholo by courtesy of American Toll Bridge Co.) 



the foremost of the United States. In the course of time a vast number of substruc- 

 ture materials and methods has been tested, but the field of successful survival is 

 narrowing down to a comparatively few. These, however, supply a sufficient variety 

 to fit most conditions. Means have been developed for the practical use of timber, 

 of timber combined with other materials and of substitutes for timber. If no radically 

 new materials or methods have been brought to light by this investigation, it has 

 added knowledge respecting both the possibilities and the limitations of present 

 materials and methods which now makes it possible to build and maintain marine 

 structures better than in the past and adequate for all economic requirements. 



