Page 135 - Webster's Speller

7. When the verbs end in e after d, and t, the final e in the past tense and participle of the perfect tense, unites with d and forms an additional syllable, but it is dropped before ing. Thus, abate, abated, abating.
ab-di-cate, ab-di-ca-ted, ab-di-ca-ting; ded-i-cate, ded- i-ca-ted, de-di-ca-ting; med-i-tate, med-i-ta-ted, med-i- ta-ing; im-pre-cate, im-pre-ca-ted, im-pre-ca-ting; vin- di-cate, vin-di-ca-ted, vin-di-cat-ing; de-grade, de-gra- ded, de-grad-ing; suf-fo-cate, suf-fo-ca-ted, suf-fo-ca- ting; ed-u-cate, ed-u-ca-ted, ed-u-ca-ting; in-vade, in- va-ded, in-va-ding; con-cede, con-ce-ded, con-ce-ding; cor-rode, cor-ro-ded; cor-ro-ding; de-lude, de-lu-ded, de-lu-ding; in-trude, in-tru-ded, in-tru-ding; ex-plode, ex-plo-ded; ex-plo-ding; de-ride, de-ri-ded; de-ri-ding.
8. In verbs ending in e after any other consonant than d and t past tense is formed by the addition of d, and this letter with the fi- nal e may form a distinct syllable; but usually the e is not sounded. Thus abridged, is pronounced abridjd; abased, abāste. Before ing, e is dropped.
a-base, a-based, a-ba-sing; a-bridge, a-bridged, a- brid-ging; con-fine, con-fined, con-fi-ning; com-pose, com-posed, com-po-sing; re-fuse, re-fused, re-fu-sing; pro-nounce, pro-nounced, pro-noun-cing; man-age, man-aged, man-a-ging; re-joice, re-joiced; re-joi-cing; cat-e-chise, cat-e-chised; cat-e-chi-sing; com-pro-mise, com-pro-mised, com-pro-mi-sing; crit-i-cise, crit-i- cised, crit-i-ci-sing; em-bez-zle, em-bez-zled, em-bez- zling; dis-o-blige, dis-o-bliged, dis-o-bli-ging, dis-fig- ure, dis-fig-ured, dis-fi-gur-ing; un-der-val-ue, un-der- val-ued, un-der-val-u-ing.
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