Performance is a subject which, in comparison with its importance, is discussed but little by the courts as a separate topic. The question of the performance of a contract involves, in the first instance, the necessity of determining the terms of the contract. Questions of this sort are generally discussed in other connections, such as offer and acceptance,1 the formation of formal contracts,2 and of written contracts.3

In many cases the question of performance also involves the meaning of the terms of the contract. Questions of this sort are usually considered under the subject of construction,4 and the so-called parol evidence rule.5 The duty of performing covenants which are implied from the fair construction of the contract taken as a whole,6 is as imperative as the duty of performing contracts which are expressed in specific language.7 In order to perform a contract, however, it is not necessary to do acts which are not required by the contract either by express language or by fair implication, although the doing of such acts would greatly facilitate the performance of the contract.8 A contract to drill a well to such a depth that it will supply a certain quantity of water, has been held not to impose upon the contractor the risk of continuing work indefinitely or of losing all compensation in case water is not found after a reasonable depth has been reached.9 It is held that after such reasonable depth is reached, the owner must pay the agreed compensation.10

When the duty of one of the parties under the contract is thus ascertained by a determination of the terms of the contract and of the meaning of such terms, the question of what has been done under the contract is a question of fact; and in this sense performance is said to be a question of fact.11 It is true that the question whether the facts thus established amount to performance, is a question for the court, and in this sense performance is said to be a question of law;12 but most of the questions of law are, as has been pointed out already, questions of construction and the like.

1 See ch. V.

2 See ch. XXXIX.

3 See ch. XL.

4 See Sec. 2020 et seq. 5 See Sec. 2137 et seq. 6 See Sec. 2038.

7 Cox v. Chase, 95 Kan. 531, L. R. A. 1915E, 590, 148 Pac. 766; Culp v. Sand-oval, 22 N. M. 71, L. R. A. 1917A, 1157, 159 Pac. 956.

8 M. P. Smith & Sons Co. v. Trexler Lumber Co., 216 Fed. 134, L. R. A. 1915B, 1086; Lansdowne v. Reihmann, - Ky. - , 124 S. W. 353.

9 Thomas v. Kanawha Valley Traction Co., 73 W. Va. 374, 80 S. E. 476.

10 Thomas v. Kanawha Valley Traction Co., 73 W. Va. 374, 80 S. E. 47*.

Apart from questions of construction and the like, the chief question of law which arises in connection with performance is found in cases in which the established facts show a performance which is less than a technical and literal performance, and yet one which has conferred upon the adversary party the greater part of the benefits for which he bargained. This question is discussed under the head of substantial performance.13 The performance of covenants to pay money is ordinarily known as payment, and because of certain peculiarities in the law of such performance, it is discussed subsequently under the heading of payment.14

The antithesis of performance is breach. Because of the effects and consequences of breach, both as giving rise to a cause of action and as operating as a discharge of the contract, many of the questions of performance are discussed under the heading of breach,15 rather than under the heading of performance.