The harbour is by far the most important on the south coast of Ireland, and dredging operations render the quays approachable for vessels drawing 20 ft.
Gold dredging is treated by Captain C. C. Longridge in Gold Dredging, and hydraulic mining is discussed by the same author in his Hydraulic Mining.
Sigsbee, Deep-sea Sounding and Dredging (Washington, 1880); O.
In 1895 began a marked commercial revival, mainly due to the steady conversion of the colony's waste lands into pasture; the development of frozen meat and dairy exports; the continuous increase of the output of coal; the invention of gold-dredging; the revival and improvement of hemp manufacture; the exploiting of the deposits of kauri gum; the reduction in the rates of interest on mortgage money; a general rise in wages, obtained without strikes, and partially secured by law, which has increased the spending power of the working classes.
By dredging, or some form of mechanical excavator, until the formation is reached which is to support the pier; the concrete is then shot into the enclosed space from a height of about io ft., and rammed down in layers about i ft.