EXAMPLES OF WALL SECTIONS. 



"3 



5 feet 7 inches by 3 feet by 2 feet 3 inches, and the weight about 

 3J tons each. 



Beyond the sheet-piling, the rear face was formed of concrete in 

 bags, each containing a cubic yard. The bags were made to fit the 

 skips, which opened at the bottom ; when the bag was filled, the 

 canvas was laid across the top and quickly sewn up ; the skip 

 was then lowered from a gantry, and the bags placed in position 

 by divers. The hearting between the front and back faces was 



DOCK FOR ORDINARY TRAFFIC 



Aoerage High Water of Ordinary Spring Tide 



B B. Do-jctail Headers to retain 

 Intervening Masonry Panel C 



Soft Sandstone Rock 



Fio. 70. HERCULANEUM DOCK 



MASONRY FACING TO SANDSTONE ROCK 



PLAN AT A A. 

 FIG. 71. 



tilled in as the work progressed with soft concrete deposited by 

 the skips (Fig. 72). 



The outer or sea end of the foundation up to the water level was 

 formed of concrete blocks weighing 100 tons each. These blocks 

 were formed in timber moulds constructed of 3-inch planks, and 

 placed just above low water. Their size was regulated by the 

 fact that they were to be lifted by flotation before high water. 

 Each block was the full thickness of the wall, and constituted 

 a 10-feet length half the height of the foundation (Fig. 73). 



I 



ORONTO 



