In Laplandic mythology, the guardian spirits of Mount Niemi.
“From this height [Niemi, in Lapland] we had opportunity several times to see those vapours rise from the lake, which the people of the country call Haltios, and which they deem to be the guardian spirits of the mountain.” —M. de Maupertuis.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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