This section is from the book "The Law Of Contracts", by William Herbert Page. Also available from Amazon: Commercial Contracts: A Practical Guide to Deals, Contracts, Agreements and Promises.
Whether breach discharges the adversary party from further performance, depends upon the relation between the stipulations entered into and not performed by the other party who breaks the contract, and the stipulations entered into by the adversary party, for the discharge of which such breach is invoked. Stipulations or covenants entered into by the respective parties to the contract may be: (1) Independent of each other; or (2) Mutually dependent, one upon the other. The question of whether covenants are dependent or independent, is a question of the intention of the parties as deduced from the terms of the contract. If the parties intend that performance by each of them is in no way conditioned upon performance by the other, the covenants are independent. If the parties intend performance by one to be conditioned upon performance by the other, the covenants are mutually dependent. Covenants which are mutually dependent may bear to each other one of two relations: (1) They may be the one precedent and the other subsequent; or (2) They may be concurrent. If the parties intend that a covenant by A is to be performed before a covenant by B is to be performed, A's covenant is precedent, and B's is subsequent; the two being mutually dependent. "Where the undertaking on one side is in terms a condition to the stipulation of the other, that is. whtre the contract provides for the performance of some act or the happening of some event and the obligations of the contract are made to depend on such performance or happening; the conditions are conditions precedent. The reason and sense of the contemplated transaction, as it must have been understood by the parties and is to be determined from the whole contract, determine whether this is so or not; or it may be determined from the nature of the acts to be done and the order in which they must necessarily precede and follow each other in the progress of performance."1 If the parties intend that performance by A of the covenant entered into by him is to be made at the same time that B is to perform the covenant entered into by him, A's covenant and B's are concurrent.
15 Bagby & Rivers Co. v. Rivers, 87 Md. 400; 67 Am. St. Rep. 357; 40 L. R. A. 632; 40 Atl. 171.
16 Ragsdale v. Xagle. 106 Cal. 332; 39 Pac. 628.
17 Drown v. Forrest, 63 Vt. 537; 14 L. R. A. 80; 22 Atl. 612. Fa-similar facts see Seudder v. Kilfo.i, 57 N. J. Eq. 171; 40 Atl. 602.
18 Ranft v. Reimers, 200 111. 386: 60 L. R. A. 291; 65 X. E. 720.
19 Symonds v. Jones, 82 Me. 302; 17 Am. St. Rep. 485; 8 L. R. A. 570; 19 Atl. 820; Grow v. Seligman, 47 Mich. 607; 41 Am. Rep. 737; 11 N. W. 404.
20 Linn County Abstract Ho, v Beeeliley. - la. - ; 99 N. W. 762.