Maelstrom (Norw. malestrom, grinding or whirling stream), an ocean current or whirlpool off the coast of Norway S. W. of the Loffoden islands, in lat. 67° 48' N. and lon. 12° E. It runs between the islands of Vaer and Moskenes, or rather between Moskenes and a large solitary rock which lies in the middle of the strait dividing Moskenes from Vaer. It is produced by the currents of the Great West fiord. The old account of this whirlpool represents it as terrific, swallowing down ships and even whales; but thiswas mere exaggeration. According to a statement (1859) by Hagerup, minister of the Norwegian marine, and by Major Vibe, superintendent of the Norwegian hydro-graphic surveys, who personally examined the Maelstrom and made official reports upon it, when the wind is steady and not too violent, boats may venture upon the whirlpool in summer at flood or ebb tide, when it is still for about half an hour. At the point half way between flood and ebb it is most violent, and boats would then be in danger. At certain times it may be passed at any state of the tide by steamers and by large ships with a steady wind.

But in winter and in storms it would be highly dangerous for any vessel to attempt to pass the Maelstrom. During a storm blowing from the west, the stream in winter runs continually to the east at the rate of six knots an hour, without changing its direction with the rising or falling tide; and if at such a time the tide is rising, the stream becomes entirely unnavigable. At certain states of the wind and tide in winter the whole stream boils in mighty whirls, against which the largest steamer could not successfully contend. These whirls, however, would not draw vessels to the bottom as was formerly believed, but would destroy them by dashing them against the rocks, or in case of small vessels by filling them and thus causing them to founder. There is no reason to suppose that the Maelstrom has been changed by any convulsion, or by the wearing away of the rocks.