GLASGOW DOCK. 



205 



on the fourth side it was omitted, leaving the iron plates of the 

 caisson next the dock. By means of piles and close boarding, 

 the two ends of the space between the iron casing of the caisson 

 and the side of the 

 dock were first closed. 

 The small pocket thus 

 formed was then 

 cleared out and filled 

 in with concrete. The 

 top of the well was 

 then closed by an iron 

 platform, bedded on in- 

 diarubber, to ensure a 

 water-tight joint. An 

 air-lock was attached 

 to the platform, which 

 was then covered with 

 concrete and ballast- 

 ing, with a weight 

 sufficient to resist the 

 pressure. The iron 



casing of the caisson FIG. 190. 



and the concrete out- 

 side was then cut through for the culvert, which was lined 

 with brickwork laid in cement, forming a solid connection with 

 the old foundation and side of the dock. The only work then 

 remaining to be done was to drive a heading through the 

 intervening old masoniy, and to line it with brickwork in cement 

 (Fig. 190). 



No. 2 Dock, Glasgow. 1 This dock, completed in 1886, from 

 the designs of, and under the superintendence of Mr. J. 

 Deas, C.E., is of the following dimensions : 



Ft. In. 



Length on floor inside of caisson ... 575 



Width at top 92 



bottom 52 4 



Width of entrance at top 67 



bottom 57 6 



Depth of water on centre of sill at high- water springs ... 22 10 



Borings taken over the site of the works proved the strata 

 to consist of sand, clay, and gravel in about equal proportions. 



1 Engineering, vol. xlii p. 566. 



