in the animal economy, is the dissolution of the aliments into such minute parts as are fit to enter the lacteal vessels, and to circulate with the mass of blood.

in Chemistry, is an operation which consists in exposing bodies to a gentle heat in proper vessels, and during a certain time. This operation is very useful in favouring the action of certain substances upon each other; as, for example, of well calcined, dry, fixed alkali upon rectified spirit of wine. When these two substances are digested together in a matrass, with a gentle sand-bath heat, the spirit of wine acquires a reddish-yellow colour and an alkaline quality. The spirit would not so well acquire these qualities by a stronger and shorter heat.