FILTER n.
Any porous substance, as cloth, paper, sand, or charcoal, through which water or other liquid may passed to cleanse it from the solid or impure matter held in suspension; a chamber or device containing such substance; a strainer; also, a similar device for purifying air. Filter bed, a pond, the bottom of which is a fil…
FLASK n.
The wooden or iron frame which holds the sand, etc., forming the mold used in a foundry; it consists of two or more parts; viz., the cope or top; sometimes, the cheeks, or middle part; and the drag, or bottom part. When there are one or more cheeks, the flask is called a three part flask, four part flask, etc. Erlenmey…