-es (gen. sing., nom. plur., and adverbial) is in disyllables (a) as a rule treated as a full syllable, e.g. Ac þét we dóþ for gódes lúue Moral Ode 56; from éuery shíres énde Chauc. Prol. 15; And élles cértain wére thei to blame ib. 375; (b) seldom syncopated or slurred over, e.g. Ure álre hláuerd fór his þrélles Moral Ode, 189; He mákede físses in þére sé ib. 83; I sáugh his sléves purfíled Chauc. Prol. 193; The ármes of dáun Arcíte id. Kn. Tale, 2033; Or élles it wás id. Sq. Tale, 209.
In trisyllables the reverse is the case; only Orm, who always, as is well known, carefully counts his syllables, treats the ending as a full syllable. Otherwise syncopation or slurring over of the last syllable is the rule in these words: a sómeres dáy Chauc. Sq. Tale, 64; Gréyhoundes he hádde id. Prol. 190; hóusbondes át that tóun id. Kn. Tale, 78; the távernes wél id. Prol. 240.
In Modern English in all these cases elision of the -e is the rule, those, of course, excepted in which the -e is still sounded at the present day (after sibilants, dentals, &c.) and which therefore we need not discuss here. The use of -es as a full syllable is otherwise quite exceptional, chiefly occurring in the Early Modern English poets, who use the sounded e, occasionally, to gain an unaccented syllable, e.g.:
The níghtës cár the stárs abóut doth bríng. Surrey, p. 15.
Sometíme to líve in lóvës blíss. Wyatt, p. 119.
That líke would nót for áll this wórldës wealth.
Spens. F. Q. I. ix. 31.
The héat doth stráight forsáke the límbës cóld. Wyatt, p. 205.
Bé your éyës yét moon-próofe. Ben Jonson, i. 979.
The usual sound of these words is night’s, love’s, world’s, limbs, eyes, and so in all similar cases.