Those made in a contract or agreement upon which one party has a right of action against the other for any injury sustained by him by reason of a breach of the cove nants or promises in his favor, and where an allegation of non-performance of his covenant by the plaintiff is no defence to such action. When the performance of one depends or is conditional on the prior performance of the other, the agreements or covenants are said to be dependent. 4 Rawle 26; 5 Wend. 496. Where performance of each is dependent or conditional upon perform- ance of the other, they are mutually de- pendent. Where there are promises on both sides in an agreement, executory considera- tions, it always becomes a question whether one party is bound to perform his before the opposite party shall be required to perform those on his side. When the agreements are dependent, neither party is bound actually to perform his part of the agreement to entitle him to an action for a breach by the other; it is enough that he was able to perform his part and offered to do so; 14 Conn. 479; 14 Me. 476; 15 La. Ann. 675. Where the consideration is executory, technically speaking, the promise and not the performance is the consideration, and hence the obligation of one may be inde- pendent of the performance of the other. Upon examination and proper construction of mutual promises, it may appear "that the obligation of the one promise is made expressly or impliedly conditional upon the due performance of the other; and then the performance of the promise, constitut- ing the executory consideration, is a condi- tion precedent to the liability to perform the other promise; in the latter case the mutual promises are called dependent, and in the former they are called independent." Leake, Cont. 344. In Jones v. Barkley, 2 Dougl. 684, Lord Mansfield thus classified mutual promises: "There are three kinds of covenants. 1. Such as are called mutual and inde- pendent, where either party may recover damages from the other for the injury he may have received by a breach of the covenants in his favor, and where it is no excuse for the defendant to allege a breach of the covenants on the part of the plain- tiff. 2. There are covenants which are conditions and dependent, in which the performance of one depends on the prior performance of another, and, therefore, till this prior condition is performed, the other party is not liable to an action on his covenants. 3. There is also a third sort of covenants, which are mutual conditions to be performed at the same time; and, in these, if one party was ready, and offered, to perform his part, and the other neglected, or refused, to perform his, he who was ready and offered has fulfilled his engage- ment, and may maintain an action for the default of the other; though it is not cer- tain that either is obliged to do the first act." In this case, it was clearly laid down that the criterion by which it is deter- mined whether promises are dependent or not, is the intention of the parties, and this is to be determined from the whole con- tract; id.; 2 W. & S. 227; 4 id. 527; 13 How. 307; 3 Bing. N. S. 355; 29 L. J. C. P. 253; 30 id. 65; or as Lord Kenyon aptly says, "It must depend on the good sense of the case; " 6 Term 570. The rule was clearly stated in a recent case: "The question whether covenants are dependent or inde- pendent must be determined in each case upon the proper construction to be placed on the language employed by the parties to express their agreement. If the language is clear and unambiguous it must be taken according to its plain meaning as ex- pressive of the intention of the parties, and, under settled principles of judicial decision, should not be controlled by the supposed inconvenience or hardship that may follow such construction. If the parties think proper, they may agree that the right of one to maintain an action against another shall be conditional or dependent upon the plaintiff's performance of covenants en- tered into on his part. On the other hand, they may agree that the performance by one shall be a condition precedent to the performance by the other. The question in each case is, which intent is disclosed by the language employed in the contract;" 153 U. S. 564, 576; and the intention is to be discovered from the order of time in which the acts are to be done, rather than from the construction of the agreement or the arrangement of the words; 4 Wash. C. C. 714; 6 Harr. & J. 85. See also 11 Pick. 151; 2 Cush. 287; 26 Conn. 176; 6 Gray 407. It is said that the dependency may be expressed or implied, as the condition is expressed or implied, and that the doctrine of implied dependency was introduced by Lord Mansfield, in Kingston v. Preston, cited in 2 Dougl. 684, before which, if there was no expressed dependency, a breach by one party was no defence to an action by the other and only gave him a cross-action; Harr. Cont. 153. What is meant by implied dependency may be briefly stated: F