ABSTRACT
13.1. After considering those types of derivation in which the kernel is used in itself unchanged or with internal change (in vowel or consonant) we shall now proceed to those types in which a formative is added either as an inflexional ending or suffix, or as a prefix. In this vast domain we meet with a great number of instances in which such an addition is accompanied by an internal change. This may be due to pre-historic vowel-changes like apophony (ablaut, gradation), or to the later mutation (umlaut), or finally to a great many changes in historical times; the latter were dealt with historically in vol I. It would be impracticable here to give a complete systematic treatment of such changes, but they will be dealt with in connexion with the sound or sounds added before or after the kernel.
