EXAMPLES OF WALL SECTIONS. 135 



Deas, to form the wharf wall at the entrance to the New 

 Cessnoch Docks. In this case, an additional precaution was 

 taken at the curves to tie the cylinders together with ordinary 

 steel rails in the manner shown by Fig. 102. The total depth 

 in this case to the bottom of the cylinders was 35 feet from the 

 coping level, so as to admit of a depth of 25 feet at low water 

 being obtained. 



In this case the walls above the cylinder were constructed 

 of granolithic-faced concrete ashlar, the face being 6 inches thick, 

 chamfered on both upper and under edges. The face blocks were 

 made 4 feet long by 2 feet deep on the bed, whilst the courses 

 ranged from 15 to 18 inches deep. Two stretchers were laid to 

 one header. The backing to the ashlar face was constructed of 

 heavy rubble, ranging from J cwt. to 2 tons, set in 5 to 1 con- 

 crete, finished with a coping 3 feet 6 inches broad, 15 inches 

 deep, and in lengths of not less than 4 feet. 



To keep the walls in position when the material was dredged 

 from the front, 2J-inch iron tie-rods, secured to heavy blocks of 

 concrete 12 feet by 8 feet by 6 feet were introduced at intervals 

 of 50 feet. 



Fig. 105 shows the ordinary construction of quay walls 

 adopted at the Queen's Dock, Glasgow, when the foundation 

 was on the boulder clay. 



Danube Improvements. 1 Fig. 106 shows the section of wall 

 adopted in forming the quay walls in the new channel through 

 the flat alluvial lands near Vienna. 



The walls are founded on concrete bases 12 feet 6 inches 

 deep by 13 feet 6 inches wide, confined within continuous 

 sheet-piling front and back, the timbers in the former 

 being 12 inches square in section, and in the latter, half 

 timbers. 



The height of the coping above zero or datum is 12 feet 

 6 inches, and the bottom of the foundation trench 14 feet 6 inches 

 below zero, making a total height of 27 feet. 



The face of the wall is of granite ashlar/in courses 1 foot 

 9 inches in depth, backed with rubble masonry ; the coping is 

 also of granite, 2 feet thick. 



The face has a batter of 1 in 10, and is set back from the 

 front of the concrete base about 2 feet. 



Quay Walls at the Port of Bordeaux. 2 The riverside quays are 

 1 Engineering. 2 Ibid., vol. xlviii. p. 679. 



