Secondly, with the advent of phonology certain immutable laws were discovered governing the sounds made by the human throat, and the way in which these sounds change with the passing of time and react upon each other when they are knit together in a spoken word. Henceforward it was possible to say for certain that, for example, the English word _wit_ (from the old verb ‘witan’, to know) was not _derived_ from the Latin ‘videre’, but cognate, or related, with it. Many words derived from ‘videre’, such as _advice_, _envy_, _review_, seem at first sight infinitely farther off from the stem ‘vid-’ than _wit_, but it was now possible for scholars to say for certain that a Latin stem ‘vid’ adopted into English could not possibly have changed into _wit_. They could be equally certain that, if the Romans had _borrowed_ the Greek word ‘idein’ (to see) into their language, it could never have changed its form to ‘_vid_ere’, so that, innumerable as are the words which Rome borrowed from Greece, ‘videre’ is not one of them. Thus, it was clear that such groups of three words as _idein_, _videre_, and _wit_, or _astēr_, _stella_, and _star_, were not father, son, and grandson (as is the case, for instance, with _poenē_, _poena_, and _penal_), but three brothers or cousins all descended from a common ancestor with a stem something like ‘weid’ belonging to some other language. This, put very briefly and with many omissions, was the contribution made by phonology to the science of comparative philology. Perhaps it is not altogether insignificant that the study of that seemingly dull subject—phonology—should be associated in our minds with one of the most charming collection of fairy-tales in Europe. It is thanks to the labours of Jacob Grimm during the first half of the last century that we are now able to reconstruct the remote pasts of words, not, it is true, with absolute certainty, but with a degree of it which makes a chapter such as the present one worth writing. And while Grimm was burrowing into the rich, loamy soil of German speech and German folk-lore, another German scholar, Franz Bopp, was laying the foundations, with the help of this knowledge and of the results of the study of Sanskrit, of a genuinely scientific comparative philology. Nor was it long before less scholarly but more imaginative minds, such as Max Müller’s, were interpreting the meaning of their researches to a wider public.