248 NOTES ON DOCKS AND DOCK CONSTRUCTION. 



depth to clear the caisson-chamber deck, or by arranging the 

 sliding ways in a series of slopes, by which the caisson is lowered 

 as it is hauled into the chamber. 



>*< p.'jy 



END ELEVATION 

 Fio 243. 



Sliding Caissons. Figs. 242, 243 show the section of a sliding 

 caisson with a fixed deck, as adopted for closing one of tho 



