hush

A hush is a scar or channel in a mine or quarry where miners have used the force of flowing water to break rock and expose ore, moving material downslope without picks or powder. It is the physical result of a technique called hushing, in which water from a reservoir or diverted stream is held back behind a temporary dam, then suddenly released. The torrent tears into the hillside, fracturing and mobilizing the host rock and leaving behind a deep erosion trench aligned with the slope.

The method works best in soft or fractured rock and was common in alluvial and placer deposits, especially for tin and gold extraction in Devon, Cornwall, and Scotland from the medieval period into the 19th century. A single release of water could move hundreds of tons of material, exposing fresh ground for hand or animal sorting. The water that carved the hush carried the ore down into lower collection points or sluices, where gravity and further water flow separated metal from waste.

Variants and conditions

A hush could be worked repeatedly by damming and releasing new channels, creating an increasingly ravaged landscape. Fresh water sources were essential, so hushing thrived in hilly terrain with reliable springs or streams. In areas where water was scarce, the technique was impractical. Some hushes remain visible today as deep, straight scars on hillsides, often overgrown, and they are valued by archaeologists as evidence of historical mining activity and the scale of medieval extraction.

The economics of hushing depended on the richness of the ore and the cost of water infrastructure. Hushing required minimal ongoing labour once the dam was built and released, making it attractive where wages were high relative to ore value. However, the loss of water to erosion and the unpredictable results of each release made the method unreliable for precise work. It fell out of use as hydraulic mining and later steam-powered excavation became cheaper and more controllable.