Various attempts have been made to explain and to classify the cases where promisors are held liable without present consideration; and so far as possible to harmonize them with recognized principles. Three explanations in particular have been given. First, - that a new promise may revive liability based on a former valid consideration, but barred by some rule of positive law. Second, - that there is in these cases a waiver of defence and the plaintiff's right is based on the original cause of action. Third, - that the plaintiff's defence to the original cause of action was from the outset defeasible and has subsequently been defeated. These explanations have value if, and only if they fit the existing law and can be applied to new cases as they come up with correct results. That they have not this value will be evident from the ensuing sections. The truth should be recognized that the cases in question in the main are survivals of the early he has failed to repudiate, he has tacitly confirmed. But it is apparent that the reasons for such a rule do not apply with equal force in favor of the agent himself, who has wrongfully committed the unauthorised act." 8 See as to the adoption of forged instruments, infra, Sec.1145; and as to ratification of alteration, infra, Sec.Sec. 1896, 1897.

9 Copps v. Henaley, 23 Okl. 311, 100 Pao. 515; Edwards v. Heralds of liberty, (Pa. 1919), 107 Atl. 324. See infra, Sec. 1145.