Those words which we have instanced as being common to English and German, both we and the Germans have got by inheritance from an earlier language. Yet there are in English hundreds of words which are not acquired by inheritance from other languages, but merely by adoption; hundreds of words have been taken directly from the Latin, or from the Latin through the French, or from the Greek, and not derived from any early language which was the parent of the Latin, Greek, and English. How shall we distinguish between these classes of words? We answer, in the first place, that the _simpler_ words are almost sure to be inherited, because people, in however rude a state they were, could never have done without words to express such everyday ideas as _to have_, _to be_, _to laugh_, _to make_, _to kill_--_I_, _thou_, _to_, _for_, _and_; whereas they might have done well enough without words such as _government_, _literature_, _sensation_, _expression_, words which express either things which were quite out of the way of these primitive people, or commonish ideas in a somewhat grand and abstract form. One of our rules, therefore, must be to begin by choosing the commoner class of words, or, generally speaking, those words which are pretty sure never to have fallen out of use, and which therefore must have been handed down from father to son. There is another rule--that those languages must be classed together which have like grammatical forms. This is the rule of especial importance in distinguishing a complete family of languages. For when once a language has got into the inflected stage, though it may hereafter lose or greatly modify nearly all its inflexions, it never either sinks back into the agglutinative stage, or adopts the grammatical forms of another language which is also in the inflected condition. These are the general rules, therefore, upon which we go. We look first for the grammatical forms and then for the simple roots, and according to the resemblance or want of resemblance between them we decide whether two tongues have any relationship, and whether that relationship is near or distant. * * * * * [Sidenote: The Semitic races.]