It is obvious that there is neither mutuality of obligation nor of remedy in a unilateral contract, and in a bilateral contract after performance by one party there necessarily ceases to be any such mutuality. Nevertheless unilateral contracts may be specifically enforced.98 The supposed rule of mutuality as stated by Fry requires that the contract at its inception should be capable of specific enforcement on both sides. If so a promise to convey land or do any other act of a nature which equity specifically enforces could not be enforced if the consideration was a counter promise to render services or to do any other acts of a nature which equity does not attempt to enforce, even though the counter-performance had been rendered. There is no propriety in such a rule, - and no good reason can be given to support it, or to distinguish the case from a contract, unilateral at the outset, to convey land; and in fact the cases are not distinguished. The promise for which specific performance is appropriate is enforced if the counter-promise or so much of it as is incapable of specific enforcement has been performed.99 The case upon which Fry bases his statement to the contrary 1 from which subsequent mistaken statements have followed was a decision concerning an illegal contract, and the court rightly held that the fact that the illegal portion of the contract had been performed would not induce it to enforce what had been promised in return. The enforcement by equity of confessedly gratuitous promises to convey land, because the promisee has entered and made improvements2 shows even more strongly that it is not a condition of specific performance that the plaintiff shall at any time have been under a specifically enforceable obligation to the defendant.
98 Palmer v. Scott, 1 Russ. & M. 381; Wilks v. Georgia Pacific R. Co., 79 Ala. 180; Davis v. Williams, 121 Ala. 542, 25 So. 704; Spires v. Urbahn, 124 CaL 110, 56 Pac. 794; Frue v. Houghton, 6 Colo. 318; Perkins r. Hadaefl, 50 HI. 216; Western R. Corporation v. Babcock, 6 Met. 346; Welch v. Whelpley, 62 Mich. 15, 28 N. W. 744, 4 Am. St. Rep. 810; Boyd v. Brown, 47 W. Va. 238, 34 S. E. fl07.
99 Wilkinson v. Clements, L. R. 8 Ch. 96; Lane v. May etc. Co., 121 Ala. 296, 25 So. 809; Thurber v. Meves, 119 Cal. 35, 50 Pac. 1063, 51 Pac 536; Lindsay v. Waraock,
93 Ga. 619, 21 S. E. 127; Denlar v. Hill, 123 Ind. 68, 24 N. E. 170; Minneapolis Ac. R. v. Cox, 76 la. 306, 41 N. W. 24, 14 Am. St. 216; Topeka Ac. Co. v. Root, 56 Kan. 187, 42 Pac. 715; Dickson v. Stewart, 71 Neb. 424, 98 N. W. 1085, 115 Am. St. Rep. 596; Safford v. Barber, 74 N. J. Eq. 352, 70 AtL 371; Asberry v. Mitchell, 121 Va. 276, 93 S. E. 638. Cf. Norris v. Fox, 45 Fed. 406; Pant-ages v. Grauman, 191 Fed. 317, 323, 112 C. C. A. 61; Wadick v. Mace, 191 N. Y. 1, 83 N. E. 571.
1Fry, Spec. Perf., Sec.463, citing Hope v. Hope, 8 De G. M. & G. 731, 746.