If in the English language we take such a word as _fathers_, we are enabled to divide it into two parts; in other words, to reduce it into two elements. By comparing it with the word _father_, we see that the s is neither part nor parcel of the original word. Hence the word is capable of being analysed; _father_ being the original primitive word, and s the secondary superadded termination. From the word _father_, the word _fathers_ is _derived_, or (changing the expression) deduced, or descended. What has been said of the word _fathers_ may also be said of _fatherly_, _fatherlike_, _fatherless_, &c. Now, from the word _father_, all these words (_fathers_, _fatherly_, _fatherlike_, and _fatherless_) differ in form and in meaning. To become such a word as _fathers_, &c., the word _father_ is _changed_. Of changes of this sort, it is the province of etymology to take cognizance. § 177. Compared with the form _fathers_, the word _father_ is the older form of the two. The word _father_ is a word current in this the nineteenth century. The same word is found much earlier, under different forms, and in different languages. Thus, in the Latin language, the form was _pater_; in Greek, πατήρ. Now, with _father_ and _fathers_, the change takes place within the same language, whilst the change that takes place between _pater_ and _father_ takes place within different languages. Of changes of this latter kind it is, also, the province of etymology to take cognizance. § 178. In its widest signification, etymology takes cognizance _of the changes of the form of words_. However, as the etymology that compares the forms _fathers_ and _father_ is different from the etymology that compares _father_ and _pater_, we have, of etymology, two sorts: one dealing with the changes of form that words undergo in one and the same language (_father_, _fathers_), the other dealing with the changes that words undergo in passing from one language to another (_pater_, _father_). The first of these sorts may be called etymology in the limited sense of the word, or the etymology of the grammarian. In this case it is opposed to orthoepy, orthography, syntax, and the other parts of grammar. This is the etymology of the ensuing pages. The second may be called etymology in the wide sense of the word, _historical_ etymology, or _comparative_ etymology. § 179. It must be again repeated that the two sorts of etymology agree in one point, viz., in taking cognizance of the _changes of forms that words undergo_. Whether the change arise from grammatical reasons, as _father_, _fathers_, or from a change of language taking place in the lapse of time, as _pater_, _father_, is a matter of indifference. In the Latin _pater_, and in the English _father_, we have one of two things, either two words descended or derived from each other, or two words descended or derived from a common original source. In _fathers_ we have a formation deduced from the radical word _father_.