period the mutation was carried through in all dialects.  The typical Old High German forms are singular fuoss, plural fuossi;[145] singular mus, plural musi.  The corresponding Middle High German forms are fuoss, fueesse; mus, muese.  Modern German Fuss:  Fuesse, Maus:  Maeuse are the regular developments of these medieval forms.  Turning to Anglo-Saxon, we find that our modern English forms correspond to fot, fet; mus, mys.[146] These forms are already in use in the earliest English monuments that we possess, dating from the eighth century, and thus antedate the Middle High German forms by three hundred years or more.  In other words, on this particular point it took German at least three hundred years to catch up with a phonetic-morphological drift[147] that had long been under way in English.  The mere fact that the affected vowels of related words (Old High German uo, Anglo-Saxon o) are not always the same shows that the affection took place at different periods in German and English.[148] There was evidently some general tendency or group of tendencies at work in early Germanic, long before English and German had developed as such, that eventually drove both of these dialects along closely parallel paths.

[Footnote 145:  I have changed the Old and Middle High German orthography slightly in order to bring it into accord with modern usage.  These purely orthographical changes are immaterial.  The u of mus is a long vowel, very nearly like the oo of English moose.]

[Footnote 146:  The vowels of these four words are long; o as in rode, e like a of fade, u like oo of brood, y like German ue.]

[Footnote 147:  Or rather stage in a drift.]

[Footnote 148:  Anglo-Saxon fet is “unrounded” from an older foet, which is phonetically related to fot precisely as is mys (i.e., mues) to mus.  Middle High German ue (Modern German u) did not develop from an “umlauted” prototype of Old High German uo and Anglo-Saxon o, but was based directly on the dialectic uo.  The unaffected prototype was long o.  Had this been affected in the earliest Germanic or West-Germanic period, we should have had a pre-German alternation fot:  foeti; this older oe could not well have resulted in ue.  Fortunately we do not need inferential evidence in this case, yet inferential comparative methods, if handled with care, may be exceedingly useful.  They are indeed indispensable to the historian of language.]