Eider-Down. Down or soft feathers of the eider-duck, such as the bird plucks from its own breast to line the nest or cover the eggs. The commercial down is chiefly obtained from this species of duck, and is used in the manufacture of many beautiful fabrics, as coverlets, robes, tippets, boas, muffs, etc. The down is one of the very poorest conductors of heat, as well as an extremely light substance, thus preserving great warmth with very little weight, and is by far the most valuable of any down-feathers imported. The eider-ducks build their nests in great numbers in almost inaccessible rocky situations on the coast of Ireland, Scotland, Lapland and Spitzbergen; and these nests are, at great risk of life, annually plundered of their down by fowlers. Eider-down comes to this country in the form of balls weighing three or four pounds. It is so fine and soft that if one of these balls is spread and warmed over hot coals it will expand and fill a bed big enough for two persons. Eider-down is only used as a covering for beds, and never should be slept upon, as it thereby loses its elasticity. The down procured from the nests, being plucked by the duck from her own breast, is most valued, and is known as "live down," that plucked from the dead bird is much less elastic, and consequently lightly esteemed. About half a pound is the quantity usually procured from each nest.