The Tangie (also spelt tongie) is a malevolent shape-shifting water spirit native to the Northern Isles, its name derived from 'tang' — the seaweed of the genus Fucus that coats its body in both forms. It most commonly appears either as a rough-haired, seaweed-drenched horse waiting at the roadside near a loch, or as a wild and matted old man who approaches travellers, apparently in need of help. Both forms are equally dangerous: like the kelpie further south, anyone who mounts the horse-form or allows the man-form to draw close is liable to be carried beneath the surface and devoured.
The story
The Tangie is considered particularly dangerous to women travelling alone after dark, and unlike the kelpie it is also credited with causing a form of supernatural disorientation — a kind of madness that overcomes both humans and animals near its haunts, making victims easier to capture. This element has parallels in the Shetland njuggle (a water horse already in the dataset) but the Tangie is the specifically Orkney variant, distinct enough in character and origin to merit a separate entry. Its roots appear to lie in Norse mythology adapted to island conditions: the Norse word tangi ('spit of land, cape') may have provided the name, with troll-like attributes from Scandinavian tradition blending into the local Orcadian spirit world.
The Tangie was collected and described in nineteenth-century Scottish folklore compendia alongside the trow (its terrestrial fairy counterpart in Orkney), and receives coverage in Walter Traill Dennison's Orkney folklore collections. It is distinct from the Finfolk, selkies, and each-uisge that populate other parts of the Scottish Islands' supernatural bestiary.