Comparative Historical Linguistics is the diachronic study of languages based on comparison between two or more languages. Descriptive linguistics studies the characteristics of language systems or dialects at given points in their histories, while historical and comparative linguistics describes changes in language systems over periods of time and considers the familial and genealogical relationships of languages. Adopting a historical approach to the study of language, it traces the evolution of languages and, by comparing one with another, establishes relationships between them.
The historical linguist therefore, is paleontologist of language from a few surviving clues, and the extrapolation of the principles of historical. Linguistics, he attempts “to reconstruct languages that have now disappeared. He also divides languages into famines based on phonological and morphological resemblances the transformational generative approach to language change says that it is not languages that change, but rather grammars. Generative linguists have been slow to take up significant work in historical linguistics, and the literature of subject to date is rather limited.
Scope OF COMPARATIVE HISTORICAL LINGUISTICS
Comparative historical linguistics tries to prove that a language is derived from an earlier language, and that particular words in it are derived from particular earlier words. Another concern of the historical linguist is to understand how languages change. By a long series of historical processes the Proto-Indo-European parent language gradually split up into a number of separate languages such as Germanic, Celtic, Slavic and these in turn evolved into their numerous modern descendants. The same process of change are responsible from the diversity of dialects within Englishand after some millennia they may well have resulted in a number of languages descended from English in just the same way that English, German, etc., are descended from Proto- Germanic. The nature of these processes stands as the question basic to all further work in historical linguistics.
Linguists compare languages for several reasons, e.g. to note their dissimilarities; to form the classification of languages into different types; to find out what language have developed from what other languages. Three areas of comparative historical linguistics are of special interest, establishment of language families on the basis of comparison between languages or/and dialects. According to Millet, the science of comparative linguistics is interested in three things: ‘phonetic laws,’ analogy and loan words’ (i.e. words taken into a given language from another language).
The comparative linguistics is thus a rigorous method of finding and testing ‘a system of correspondences between an initial language and languages arising at a later period.’ Comparative linguistics may also lead to & explanation of how and why certain changes took place in a certain order, in turn creating certain languages