In the converse case where the contract was originally legal, but because of a change in purpose of the parties, or a change in the law, performance of the acts contracted for on one side or the other has become illegal, any subsequent performance of such acts is against public policy and the party who has undertaken to perform them is excused from so doing.55 If in spite of the legal prohibition he still performs, he cannot recover what was promised him in return therefor.56 Where, however, that portion of the performance of the contract which is prohibited, has already been performed before the prohibition, the remainder of the contract is not invalidated by the prohibition, and may be enforced.57 Likewise, if a sale has been completely 52See eases of contracts made on Sunday, and subsequently performed on a secular day. Supra, Sec. Sec. 1704, 1707; Cones v. The United States, 8 Ct. CI. 421. In this case a contract was made for the sale of cotton within the enemy's country, but the sale was subsequently carried out within the Union lines. The sale was legal and the property passed.

53 Lanning v. Osborne, 82 Fed. 575; Woods Sec. . Armstrong, 54 Ala. 150, 25 Am. Rep. 671; Willcox v. Edwards, 162 Cal. 455, 123 Pac. 276; Quarles v. Evans, 7 La. Ann. 543; Robinson v. Barrows, 48 Me. 186; Schaum v. Brandt 116 Md. 560, 82 Atl. 551; Springfield Bank v. Merrick, 14 Mass. 322; Roby Sec. . West, 4 N. H. 285,17 Am. Dec. 423; Puckett v. Alexander, 102 N. C. 95, 8 S. E. 767, 3 L. R. A. 43 Nichols v. Pbulson, 6 Ohio, 305. But see Washburn v. Franklin, 13 Abb. Pr. 140.

54 See supra, Sec. 1683.

55 See infra, Sec. 1938.

56 See Gray v. Sims, 3 Wash. C. C. 276; American Mercantile Exchange v. Blunt, 102 Me. 128, 66 Atl. 212, 10 L. R. A. (N. S.) 414, 120 Am. St. 463.

57 In Anheuser-Busch Brewing Assoc. v. Bond, 66 Fed. 653, 13 C. C. A. 655, 32 U. S. App. 38, a debt arising from sales of lager beer in Indian Territory carried out, the subsequent agreement of the parties to utilize the property sold for ah illegal purpose will not deprive the seller of his right to recover the price.58