It is not the breach of every covenant of a contract that may operate as a discharge of the adversary party. To have this effect the covenant broken must be a vital term of the contract, breach of which makes performance impracticable, and the accomplishment of the purpose of the contract impossible. Breach of a minor and subsidiary covenant may give rise to an action for damages but it can not operate as a discharge.1 If A has agreed to sell land to B, in consideration of which B is to pay to A one half of the crops for a certain period of time, a small and unintentional shortage on B's part does not give A the right to avoid such contract.2 If A agrees to make advances to B to the amount of B's expenses under the contract, and A has furnished about two-thirds of B's expenses and suggests an arbitration as to A's liability to advance more, B can not treat such conduct on the part of A as discharging him from further liability under the contract.3 If A assigns an invention to B under an agreement by which B is to take out a patent thereon and to pay a certain amount to A, B's conduct in dropping A's claim and taking out a patent on a similar invention in his own name does not discharge B from his duty to pay A, as long as he has retained A's rights under such assignment without regard to the actual merits of A's invention.4 A contract to erect and maintain a mill is not discharged by the adversary party's failure to maintain it for the entire time, but an action for damages is the only remedy.5 Similar results have been reached where a contract to construct waterworks is departed from in minor points and no opportunity has been given to the water company to correct them; 6 where a contract to feed cattle is broken only by a failure to construct racks to save the hay, the owner having suffered no loss thereby;7 and where a contract to ship goods under the vendee's form of charter party is broken only by using another form of charter party which omits a clause that if the vessel is freed from wharfage during discharge of cargo, freight is to be reduced four and a half pence per ton.8 In all these cases the party not in default must perform and sue for damages if he has suffered any. Whether a partial breach operates as a discharge depends on the relation of the covenant which has been broken to the rest of the contract, on the question of the adequacy of compensation in damages and on the rules of local procedure allowing partial defenses to be made.9

16 Winfield Lumber Co. v. Partridge, - Ala. -, 80 So. 821.

17 Acme Food Co. v. Older, 04 W. Va. 255, 17 L. R. A. (N.S.) 807, 61 S. E. 235.

18 Acme Food Co. v. Older, 64 W. Va. 255, 17 L. R. A. (N.S.) 807, 61 S. E. 235.

1 United States. Eclipse Bicycle Co. v. Farrow, 190 U. S. 581, 50 L. ed. 317; Robertson v. Gordon, 226 U. S. 311, 57 L. ed. 236; Hansen v. Storage Co., 86 Fed. 832.

California. Lassing v. James, 107 Cal. 348, 40 Pac. 534; Withers v. Moore (Cal.), 71 Pac. 697.

Idaho. Daniels v. Englehart, 18 Ida. 548, 39 L. R. A. (N.S.) 938, 111 Pac. 3.

Illinois. Lake Shore, etc., Co. v. Richards, 152 111. 59, 30 L. R. A. 33, 38 N. E. 773; Anglo-Wyoming Oil Fields v. Miller, 216 111. 272, 74 N. E. 821; Bloomington Hotel Co. v. Garth-wait, 227 111. 613, 81 N. E. 714.

Iowa. Graves v. Gas Co., 83 la. 714, 50 N.W. 283; Galt v. Provan, 131 la. 277, 108 N. W. 760.

Kansas. Missouri, K. & T. Ry. v. Ft. Scott, 15 Kan. 435.

Kentucky. Smith v. Howard (Ky.), 105 S. W. 411, 32 Ky. L. Rep. 211.

Maryland. Nes v. Union Trust Co., 104 AW. 15, 64 Atl. 310; Schnepfe v. Schnepfe, 124 Md. 330, 92 Atl. 891; Ady v. Jenkins, 133 Md. 36, 104 Atl. 178.

Massachusetts. Leavitt v. Fletcher, 92 Mass. (10 All.) 119; Lund v. Smith, 191 Mass. 473, 77 N. E. 893.

Michigan. Alderton v. Williams, 139 Mich. 296, 102 N. W. 753; Gates v. Detroit & Mackinac Ry., 147 Mich. 523, 111 N. W. 101.

Minnesota. Hunter v. Holmes, 60 Minn. 496, 62 N. W. 1131.

Missouri. Drummond Realty & Investment Co. v. W. H. Thompson Trust Co. (Mo.), 178 S. W. 479.

Nebraska. Swobe v. Electric Light Co., 39 Neb. 586, 58 N. W. 181.

New Hampshire. Smart v. Gale, 62 N. H. 62.

New Jersey. United & Globe Rubber Mfg. Co. v. Conard, 80 X. J. L. 286, 78 AtL 203.

New York. Tracy v. Albany Exchange Co., 7 N. Y. 472, 57 Am. Dec. 538; St. Regis Paper Co. v. Santa

Clara Lumber Co., 180 N. Y. 89, 78 N. E. 701.

North Dakota. Gage v. Fisher, 5 N. D. 297, 31 L. R. A. 667, 65 N. W. 809; Bennett v. Glaspell, 15 N. D. 239, 107 N. W. 45.

Oregon. Fargo v. Wade, 72 Or. 477, L. R. A. 1915A, 271, 142 Pac. 830.

Tennessee. Bradford v. Montgomery Furniture Co., 115 Tenn. 610, 9 L. R. A. (N.S.) 979, 92 S. W. 1104.

West Virginia. Carper v. United Fuel Gas Co., 78 W. Va. 433, L. R. A. 1917A, 171, 89 S. E. 12.

Wisconsin. Mueller v. Cook, 126 Wis. 504, 105 N. W. 1054; Danielson v. Danielson, 165 Wis. 171, L. R. A. 1917D, 624, 161 N. W. 787.

2 Bennett v. Glaspell, 15 N. D. 239, 107 N. W. 45.

3 St. Regis Paper Co. v. Santa Clara Lumber Co., 186 N. Y. 89, 78 N. E. 701.

4 Eclipse Bicycle Co. v. Farrow, 199 U. S. 581, 50 L. ed. 317.

5 Hunter v. Holmes, 60 Minn. 496, 62 N. W. 1131.

6 Winfield v. Water Co., 51 Kan. 70, 32 Pac. 663.

7 Lassing v. James, 107 Cal. 348, 40 Pac. 534.

8 Withers v. Moore (Oai.), 71 Pac 697.