And that is all they knew about Iceland. As a country with a political history and a literature it was no more present in their minds than as a holiday resort. Nor were any of the countries that bordered the Baltic, except on the South. But Danzig alone was enough to keep the Baltic a busy sea, and consequently Denmark was not as much ignored as would otherwise have happened; for both sides of the entrance to the Baltic belonged to the King of Denmark, whose extortions in the way of tolls kept his name before the public. Norway was thus practically isolated from Europe. Sweden, however, during the Thirty Years' War, attracted some attention, partly on account of its share in the war, partly on account of the development of its silver mines. There is an interesting account of a visit to those at "Sylfbergen," twenty leagues from Stockholm, in 1667, which may serve as an indication of experiences that might have been met with at an earlier date. The visitor, a Frenchman,[57] descended, half-naked, in half a cask, which was attached to a cable by three iron chains, accompanied by two workers whose grimness, flavour, and unpleasant personalities, gave him an attack of nerves. Among the miners he found French, Germans, English, Italians and Russians, all, as he says, digging their own graves, for the conditions of mining in those days was terrible. A traveller through Hungary in 1615[58] notes that the miners there could not work more than four hours at a stretch, and that few reached middle age, what with the number of casualties and the conditions of the mines. One result of this was that they usually married at fifteen. Yet weekly wages, after making allowance for the cheapness of living in Hungary, were equivalent to no more than twelve to fourteen shillings at present values. It was a most natural question at the time to ask whether, working as they did in the bowels of the earth, they ever came across demons. To which question a miner answered that sometimes they did, and on those occasions they appeared in the shape of little black boys, chattering, but doing no harm beyond blowing the lamps out.