Thus equipped with his fixed root and the various words formed out of it, man had the rough _material_ out of which to build up all the elaborate languages which the world has known. And he continued his work something in this fashion. As generation followed generation the pronunciation of words was changed, as is constantly being done at the present day. Our grandmothers pronounced ‘Rome,’ ‘Room,’ and ‘brooch,’ as it was spelt, and not as we pronounce it--‘broach.’ And let it be remembered, before writing was invented, there was nothing but the pronunciation to fix the word, and a new pronunciation was really a new word. When there was no written form to petrify a word, these changes of pronunciation were very rapid and frequent, so that not only would each generation have a different set of words from their fathers, but probably each tribe would be partly unintelligible to its neighbouring tribes, just as a Somersetshire man is to a great extent unintelligible to a man from Yorkshire. The first result of these changes would be the springing up of that class of ‘meaningless’ words of which we spoke above. Out of some significant words, such as ‘head’ and ‘foot,’ would arise insignificant words similar to ‘over’ and ‘under.’ Such a change could only begin when of two names each for ‘head’ and ‘foot’ one became obsolete as a noun, and was only used adverbially. Then what had originally meant, metaphorically, ‘head of rock’ and ‘foot of rock’[23] might come to be used for ‘over’ and ‘under the rock,’ in exactly the same way that the word _ago_, having changed its form from _agone_, has become a ‘meaningless’ word to the Englishman of to-day. And with the acquisition of the insignificant words a new and very important process began. To understand [Sidenote: Growth of inflexions.]