Although the later contract may be made by a sufficient offer and acceptance,1 and although it is supported by sufficient consideration,2 it may be invalid and unenforceable for some other reason. If the later contract is invalid and unenforceable for any other reason, it does not abrogate an earlier contract, though it was intended so to do.3

If the second contract is invalid because of mistake as to one of the essential elements of the contract.4 such contract does not operate to modify or to discharge the prior contract.5 If the original contract is to furnish a vessel to be selected by the shipper, his subsequent act in selecting a vessel which has been lost at sea without the knowledge of either party, does not make a binding contract between the two parties, and no action can be brought thereon.6 If the second contract is entered into under a mistake as to an essential element or under a misunderstanding as to the terms, one of the parties thereto, who, on discovering such mistake, performs the original contract, may recover thereunder.7

If the second contract is voidable, as by reason of duress,8 and the second contract is avoided by reason of such defect, it will not operate to abrogate or modify the earlier contract. If the subsequent contract is invalid because it is entered into on behalf of one of the parties to the contract by an unauthorized agent, such contract can not discharge or modify the prior contract.9 A subsequent modification of a policy of insurance,10 or of a contract for the transportation of goods,11 by an unauthorized agent, has no effect upon the original contract.

2Libby v. Barry, 15 N. D. 286, 107 N. W. 072.

3Banewur v. Levenson, 171 Mass. 1, 50 N. E. 10.

1 See Sec. 2458.

2 See Sec. 2461 et seq.

3 Smith v. Miller, 79 Conn. 624, 66 Atl. 172; McCoy v. Flynn, 169 Ia. 622, L. R. .A. 1915D, 1064, 151 N. W. 465 (obiter); Furness v. Fahey, 127 Md. 333, 96 Atl. 619.

A prior debt is not affected by usurious renewals. Cain v. Bonner, 108 Tex. 399, 3 A. L. R. 874, 194 S. W. 1098.

4 See ch. IX.

5 Smith v. Miller, 79 Conn. 624, 6G

Atl 172; Furness v. Fahey, 127 Md. 333, 96 Atl. 619 [for former hearing, see Furness v. Randall, 124 Md. 101, 91 Atl. 797].

6 Furness v. Fahey, 127 Md. 333. 96 Atl. 610 [for former hearing, see Furness v. Randall, 124 Md. 101, 91 Atl. 797].

7 Smith v. Miller, 79 Conn. 624, 66 Atl. 172.

8 Weatherford v. McCrocklin (Ky.), 34 S. W. 24.

The same result follows where the second contract is voidable for fraud. Frederick v. Hillebrand, - Mich. - , 165 N. W. 810.

If the later contract is invalid because its subject-matter is void or illegal,12 it can not operate to abrogate or to modify the earlier contract.13 A subsequent contract which is invalid because it is in restraint of marriage, does not discharge a right of action growing out of a breach of a prior contract to intermarry.14

If a later contract is unenforceable because of the Statute of Frauds, it can not, if attacked on that ground, abrogate or modify an earlier contract.15