Cellars, in modern building, are the lowest rooms in a house; their ceilings are usually level with the surface of the ground, on which the house is built. They are also situated under the pavement before it, particularly in Streets and squares.

On account of the great utility of cellars in preserving wines, ale, etc. various attempts have been made to prevent the generation of damp and noxious air, in subter-raneous places : two of these merit particularly to be noticed. The first is that of M. Westbeck (in the Memoirs of the Royal Swedish Academy of the Sciences), who caus-ed a vaulted dcellar tobe constructed, without stone or lime: instead of the former, he employed charcoal, placed in the manner of brick-work : and, as a substitute for the latter, be used a cement, consisting of clay, kneaded with charcoal dust. These brittle mat. rials .. employed, because they attract no moisture, or acidity, either from the air, or earth; a circumstance which renders them even more dur-able than stone.

Another method, is that frequently practised in Germany where the vaults are so construct-ed, that a canal, or passage of com-munication, is opened from cellar to the principal chimney of the house. By this means, the lars may be continually ventilated, so as to expel the damp and noxious vapours, which are usually collect-ed in them; while the draught of the chimney is, in a considerable degree, promoted.

The dangers arising from the sodden, or frequent inhalation of such air as is often generated in close, and damp cellars, have ready been stated; together with the most proper method of obviat-ing its deleterious effects. See AIR, p.23.