A TREATISE 



ON 



DREDGES AND DREDGING 



CHAPTER I 

 DREDGING AND DREDGES 



DREDGING is the operation of excavating soils from the bottom 

 of bodies of water. It is undertaken for different purposes, chiefly for 

 deepening and widening the bed of rivers and navigable channels, or 

 for deepening harbors and bays to facilitate navigation, or preparing 

 the foundations of immense masonry structures, which should be 

 located directly on ledge rock, usually encountered far below the bed 

 of the stream. To-day dredging is also undertaken for mining and 

 other industrial purposes, as will be shown later. No matter for 

 what reason these dredging operations are undertaken, they are 

 always made by powerful machines called Dredges in America and 

 Dredgers in England, built with an efficiency proportionate to the 

 magnitude of the improvement upon which they are employed. 



Engineers and public officials frequently do not realize the 

 importance of dredging. Vast sums of money are being spent 

 for this class of work and new projects are continually being placed 

 before the public that involves dredging. Even manufacturers 

 of dredging machinery do not seem to comprehend the future great 

 development of this industry, as dredges are the means of handling 

 large quantities of raw materials as well as of making extensive 

 excavations both on land and under water. 



The principal uses of dredging machinery may be grouped 

 as follows: 



