FILTER n.
ining such substance; a strainer; also, a similar device for purifying air. Filter bed, a pond, the bottom of which is a filter composed of sand gravel. -- Filter gallery, an underground gallery or tunnel, alongside of a stream, to collect the water that filters through the intervening sand and gravel; -- called also…
FIN n.
n whale (Zoöl.), a finback. -- Paired fins (Zoöl.), the pectoral and ventral fins, corresponding to the fore and hind legs of the higher animals. -- Unpaired, or Median, fins (Zoöl.), the dorsal, caudal, and anal fins.
FLING v.
; to dart; to emit with violence as if thrown from the hand; as, to fing a stone into the pond. 'T is Fate that flings the dice: and, as she flings, Of kings makes peasants, and of peasants kings. Dryden. He . . . like Jove, his lighting flung. Dryden. I know thy generous temper well. Fling but the appearance of dishon…
FREE a.
l. -- Free bench (Eng. Law), a widow's right in the copyhold lands of her husband, corresponding to dower in freeholds. -- Free board (Naut.), a vessel's side between water line and gunwale. -- Free bond (Chem.), an unsaturated or unemployed unit, or bond, of affinity or valence, of an atom or radical. -- Free-boro…
FRICTION n.
er; as, in the illustration, the cone a on one shaft, when thrust forcibly into the corresponding hollow cone b on the other shaft, compels the shafts to rotate together, by the hold the friction of the conical surfaces gives. (b) A toothed clutch, one member of which, instead of being made fast on its shaft, is held b…