George P. Reilly


Dredging is a special type of excavation involving the removal of material from under water. Several thousand years ago the Chinese and the Assyrians employed the primitive spoon-and-bag dredger to clean and maintain their canals. This apparatus consisted of a bag manipulated from a boat by means of a pole attached to a yoke or hoop at the mouth of the bag which was dragged along the canal bottom. When full, the bag was lifted and dumped into the boat. The method of disposal of the material is not clear, but it must be assumed that it was lifted ashore or dumped overboard, all probably by hand. Little improvement over this spoon-and-bag method of dredging was made until the advent of the industrial era in the eighteenth century. The method was then developed into a chain of buckets moving on a ladder.


dredging; hopper

Full Text: PDF

Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.