Of course, adits are still useful for deeper mines because the water only needs to be raised to the drainage adit rather than to the surface.

In 1150 the Rathstiefsten Gallery, a drainage adit for the Rammelsberg mine, was completed.

Key words: deep-seated landslide, mitigation, drainage adit, distinct-element method, coupled hydromechanical analysis.

All mine workings below both the drainage adit ("below adit") and the water table will flood unless mechanical means are used for drainage.

The first really significant developments came in 1710 when Francis Bassett obtained a lease of Penhellick Vean and a drainage adit was begun.

The depth to which a mine can be drained by gravity alone is defined by the deepest open adit which is known as the "drainage adit".

To carry out a proper exploration of these veins in some depth it was necessary to have a drainage adit otherwise there would have been continual hindrance with water.

In the beginning of the 18th century the 25 mines in Sankt Andreasberg had their highest output and the deepest drainage adit Grünhirscher Stollen had reached its limit.

But even the advent of the Rothschönberger Stolln, the largest and most important Saxon drainage adit, which drained the entire Freiberg district, could not stop the decline of mining.

The 'well' shaft, situated near Folkestone Warren Halt (a disused small station) to the east of the town in a landslip area of great natural beauty, is actually an access shaft to a drainage adit.

The Milwr Tunnel is a mine drainage adit running some 10 miles from the hamlet of Cadole near Loggerheads, Denbighshire to Bagillt on the Dee Estuary in North Wales.

The grounds continued to have excess water and Lawrence, the neighbouring farmer advised that the water was coming from an old mine and there were some old filled in shafts and an old drainage adit on the farm.

Because of the great reduction in ongoing costs that a drainage adit can provide, they have sometimes been driven for great distances just for this purpose, one such being the Milwr tunnel in North Wales, which is about ten miles (16 km) long.