190 NOTES ON DOCKS AND DOCK CONSTRUCTION. 



Newfoundland, for the Colonial Government (Figs. 171, 172). 

 The dimensions of this dock are as follows : 



Ft. In. 



Greatest length on floor from head to outer gate sill 010 



inner gate sill 56!) G 



Greatest width at coping level ... 132 



on floor 49 10 



Least width of entrance at coping (inner stop) ... ... ... ... 84 9 



on floor (inner stop) 52 9 



Greatest draught of water over inner gate sill at high water of spring tides 25 



This dock is built upon spruce-fir foundation-piles, except 

 the floor, which rests upon a bed of Portland -cement concrete, 

 varying from 2J feet in depth at the head to about 6 feet at 



FIG. 172. 



the entrance. The concrete floor itself rests upon a glacial 

 deposit of compact slaty gravel immediately overlying the 

 bed rock. 



Mount Stuart Dock. An example of an abnormally wide 

 dock on the floor, which has, it is stated, proved a great success, 

 is the Mount Stuart Dock at Cardiff (Fig. 173). In this case 

 the width at coping level is 105 feet, and 90 feet wide above 

 the first altar, which is about 1 foot 3 inches above the sill 

 level. The keel blocks are arranged to accommodate two vessels 

 up to 350 feet long alongside of each other. In the event of 



