An impossibility of performing the contract is to be distinguished from an impossibility of making that use of the consideration which was contemplated at the time the contract was made. For this latter impossibility is not necessarily a good defence against a prayer for specific performance, (h)

The third kind of impossibility is that which operates through the necessary requirement in equity of a fair and equal mutuality, (i) If, therefore, the plaintiff ought himself to do something as his part of the bargain which he seeks to enforce, which thing he cannot do, (j) or even if it be something which he is bound to do, but has not done, (k) and the court cannot compel *him to do it, equity will not decree specific performance against the other party. (l) Thus if an infant bring a suit

(g) Ante,§ l,p.*358.

(h) Thus, a railway company, who had contracted to purchase certain land for the purposes of the construction of a branch road, were held not to be excused from paying the agreed price, by reason that they had allowed their powers to take and use the laud to lapse and expire by parliamentary limitation. Hawk.es v. Eastern Ry. Co. 1 l)e G, M. & G. 737, per Lord St. Leonards, Ch., affirming decision of Knight Bruce, V. C, 3 De G. & 8. 743.

(i) It is a corollary of the principle of mutuality, that what was agreed to be done on the part of the plaintiff should distinctly appear. Wingate v. Dail, 2 Harris & J. 77; Morgan v. Rainsford, 8 Irish Eq. 299.

(j) " It would be quite new," said Sir William Grant," for a court of equity to enforce performance on one side without examining whether there be a capacity to perform on the other." Fildes v. Hooker, 2 Meriv. 428. But the fact, that when the agreement was made it was subject to a contingency which might have rendered performance by the defendant impossible, constitutes no objection to the execution of the contract if the contingency did not happen. Dowell v. Dew, I Younge & C, Ch. 345. 856.

(k) Thus, where the plaintiff prayed the specific execution of an agreement for a lease, entered into a long time before, under which agreement he had entered into possession, and made expensive improvements, Sir George Turner, V. C, refused to decree a lease, on the ground that some of the covenants which it would contain had already been broken by the plaintiff, so that, had the lease been in existence, according to the agreement, the lessor would have had a right to re-enter. Gregory v. Wilson, 9 Hare, 683, 10 Eng. L. & Eq. 133. The court, in requiring something to be doue on the part of the plaintiff as a condition precedent to his obtaining the relief prayed, will sometimes go beyond the letter of the contract, and impose something which the defendant could not have demanded had he been the party applying for the interposition of the court. See Moxhay v. Inderwick, 1 De G. & S. 708. An understanding of the parties, collateral to a written contract between them, and not intended to form a part of it, cannot occasion a denial of a specific performance of the contract: but it may have the effect to induce the court not to decree a specific performance without taking care that the defendant should have the benefit of such understanding. London and Birmingham Railway Co. v. Winter, Craig & Pn. 57, 61. And see ante, § 5, p. *387.

(l) But if the thing to be done by the plaintiff did not enter very materially into the consideration of the agreement, and the defendant at the time contemplated the possibility of a failure on the plaintiff's part in that respect, and made provision for the case in the contract itself, it will be no obstacle to the grantfor specific performance, it may be a sufficient reason for denying it that there is something for him to do which he does not offer, and which the court cannot compel him to do. (m) But if the infant, after coming of age, files a bill to obtain performance of the contract, he thereby becomes bound by the contract, and the want of mutuality is cured, (n) So, if he in any other manner, affirm the contract at majority, it becomes mutual, (o) In one case the court refused to restrain a defendant from purchasing a certain commodity where he would, although he had agreed to purchase it only of the plaintiff, who sought to compel him to do so; and the ground* of the refusal was, that the court could not compel the plaintiff to supply the defendant with as much of that commodity as he might want (p)

A probable disability of the plaintiff, although he is not yet chargeable with any default, may be ground for a court of equity to refuse to interpose. Thus, if the terms of the contract require the plaintiff to pay money at a future time, his insolvency may deprive him of the right to compel the other party to perform his agreement, (q)l And it has been held, that * the insolvency of an intended lessee is a weighty objection to granting him a decree for a lease, (r)

If the nature of the duties of a servant is such that it is ing of a decree of specific performance. Lord v. Stephens, 1 Younge & C, Ex. 222; 1 Fonbl. Eq. b. i. ch. 5, § 8, note (g).

(m) Flight v. Holland, 4 Rum. 298; Hargrove v. Hargrave, 12 Beav. 411.

(n) Milliken v. Milliken, 8 Irish Eq. 16. And see Flight v. Bolland, 4 Ross. 298.

(o) See Milliken v. Milliken, 8 Irish Eq 27 28

(p) Hiils v. CroU,2 Phillips, 60. There is a more full report of the judgment of the Lord Chancellor (Lyndhurst) in a note in 1 De G., M. & G. 627. This case, which had had a great deal of doubt thrown upon it previously, was recently referred to with approval by Lord St. Leonards, Ch., Lumley v. Wagner, 1 De G., M. & G. 627.

(q) Franklin v. Lord Brownlow, 14 Yes. 556; Lord Longdate, M. R., Neale v. Mackenzie, 1 Keen, 474. And see Brashier v. Gratz, 6 Wheat. 539.

(r) Buckland v. Hall, 8 Ves. 92. The insolvency of the plaintiff has been held to be a ground for refusing a decree for a lease, although his discharge was granted as long before as six or seven years, but subsequently to the agreement. Price v. Assheton, 1 Younge & C, Ex. 444, per Alderson, B. Compare the same case at an earlier stage, before Lord Lyndhurst, C. B., 1 Younge & C, Ex. 91, 93. While it is not necessary that the party should have taken the benefit of the Insolvent Laws, or that he should have given up all his property to his creditors, there must yet be satisfactory proof of general insolvency, and a previous default in a particular instance is not enough. Neale v. Mackenzie, 1 Keen, 474.