The new contract may amount to a modification of the prior contract leaving some of its terms in force and continuing the original liability with such modifications, or it may operate as a termination of all liability under the original contract.1 Whether the new contract is a modification of the original contract, or whether it supersedes the original contract entirely and replaces it for all purposes, is a question which depends primarily upon the intent of the parties.2

If the rights of third persons are not affected, the new contract, if valid, may have either effect, according to the will of the parties expressed in such contract, and ascertained by the ordinary rules of construction.3

If the original contract is terminated rightfully by one of the parties, a subsequent contract upon the same subject-matter will be regarded as a new and independent contract, and not a modification of the original contract.4 If a public corporation is authorized by statute to terminate a contract for public improvement, and it exercises such right, and thereafter makes a new contract with the same contractor for the same improvement, the new contract will be regarded as distinct from the original contract, and it will be subject to a statute which was enacted after the first contract was made and before the second contract was made.5 If it is doubtful whether a subsequent transaction is intended to modify a prior contract or to carry it into effect, it would ordinarily be presumed that it was to carry it into effect rather than to modify it.6

5 Iowa-Minnesota Land Co. v. Conner, 136 Ia. 674, 112 N. W. 820; More-craft v. Allen, 78 N. J. L. 729, L. R. A. 1915B, 1, 76 Atl. 920.

1 Iowa. Blake v. Osmunds on, 178 Ia. 121, 159 N. W. 766.

Minnesota. Mulcahy v. Dieudonne, 103 Minn. 352, 115 N. W. 636.

North Dakota. Chesley v. Soo Lignite Coat Co., 19 N. D. 18, 121 N. W. 73.

Oregon. Aya v. Morson, 90 Or. 647, 178 Pac. 207.

Utah. Schwab Safe & Lock Co. v. Snow, 47 Utah 199, 152 Pac. 171.

Vermont. Davenport v. Crowell, 79 Vt. 419, 65 Atl. 557.

2 Maryland. District National Bank v. Mordecai, - Md. - , 105 Atl. 586.

Minnesota. Mulcahy v. Dieudonne, 103 Minn. 352, 115 N. W. 636.

New Jersey. Morecraft v. Allen, 78 N. J. L. 729, L. R. A. 1915B, 1, 75 Atl. 920.

Oregon. Aya v. Morson, 90 Or. 647, 178 Pac. 207.

Pennsylvania. Robert Grace Contracting Co. v. Norfolk & W. Ry. Co., 259 Pa. St. 241, 102 Atl. 956.

Texas. Alabama Oil & Pipe Line Co. v. Sun Co., 99 Tex. 606, 92 S. W. 253 [judgment reversed (Tex. Civ. App.), 90 S. W. 202].

3 See ch. LXIII.

4 People v. Metz, 193 N. Y. 148, 85 N. E. 1070 [order affirmed on rehearing, 86 N. E. 986].