In the neighbourhood are brine springs and a spa (Wilhelmsbad).
Many brine springs also occur in a more or less saturated condition.
One difference between the manufacture of salt from rock-salt brine as carried on in Britain and on the Continent lies in the use in the latter case of closed or covered pans, except in the making of fine salt, whereas in Britain open ones are employed.
The principal occupation is the manufacture of the salt obtained from the brine springs or wyches, to which the town probably owes both its name and its origin.
Salt, in the form of brine, is sometimes present in coal.