further comment in this connection. This subject is further amplified in the works on the "Law of Contracts," but it is not necessary to elaborate it here.

When the performance

45. Discharge by Tender. of a contract is frustrated or prevented by the act of the party to whom the performance is due, the offering to perform is called a tender. As applied to engineering contracts, if the contractor is prevented from performance by the owner, the latter subjects himself to liability on a suit for damages sustained by the contractor by not being allowed to perform. In other words, the owner breaks the contract by his refusal and subjects himself to a suit for damages, the same as in any other case of breach of contract, while the contractor stands released from all further obligation under the contract, his tender being construed as performance so far as he is concerned.

46. Kinds of Impossibility Which Will Discharge a Contract. An agreement between parties to do what both know to be impossible is discharged when their knowledge of such impossibility is shown, but where the impossibility is known only to one of the parties, he is liable for damages to the party to whom it is unknown.

Where the subject-matter is nonexistent, or has ceased to exist, the impossibility of performance results from a mutual mistake of fact, and the contract is discharged.

Where performance is rendered impossible by what is called in law "an act of God or of the public enemy" the party so contracting is excused. By "an act of God" as used in law as discharging a contract is meant a manifestation of the powers of nature over which man has no control, such as fires caused by lightning (but not by accident or other cause), winds, floods, sickness and the like. In the performance of engineering contracts unusual difficulties will not be placed in this cate

gory, so long as they are by any possibility under human

control.

While as stated above an "act of God or of the public enemy" making performance impossible, will discharge a contract, yet it must be clearly shown that such "act of God or of the public enemy" did in fact render the performance quite impossible, and not simply difficult or expensive. Thus if wind, flood, or lightning should destroy a partly completed engineering work, if it were possible to re-erect it within the time specified, the contractor would be held to full performance.

47. Kinds of So-called Impossibilities Which Will Not Discharge the Contract. "When a person contracts to do a given act he pledges himself as having the capacity to do it, and assumes the risk of being prevented from performing his contract by obstacles or accidents; against obstacles or accidents that may interfere with performance he should protect himself by contract. Having presumed generally to do a thing he can not allege that difficulties and obstacles prevented him from fulfilling his contract, although they did in fact render the doing of the thing by him impossible. He is bound to do whatever is within the scope of any human being to accomplish."

From the above which is quoted from Judge Amos Thayer, of the United States Court of Appeals, it is evident that if a contractor wishes to obtain release from full and complete performance for certain contingencies, as for instance, inability to obtain material, or to place sub-contracts, or to get the subcontractors to comply with their agreement, or to provide against labor strikes, whether in the trades or on the railroads, or against the inclemencies of the weather which might make performance within the time difficult and very expensive, or against any other of the extraordinary contingencies which may arise to prevent performance except at great loss, he must evidently provide protection for himself in the body of the con

tract. In the absence of such a protection and under a simple agreement to perform certain work within a certain time, the law will hold him to a strict compliance, so long as such compliance lies within the realm of human possibility, regardless of expense.

48. Discharge of Contract by Operation of Law. There are various methods by which a contract may be discharged through the operation of the law, as for instance, by merging one contract into another, by a fraudulent alteration of the written agreement, by the bankruptcy of one of the parties, or by death. In the case of the death of one of the parties, the contract is discharged only when this is made a condition in the contract, or when performance thus becomes impossible. It will become impossible when the performance is required to be of a personal character, as contracts for services, or such as require professional skill, marriage contracts, and the like.

49. Discharge of Contract by Breach. While any material breach of the contract on the part of either of the parties furnishes a right of action to the injured party, it is only in exceptional cases that such a breach operates to discharge fully the other party from his obligations. The contract will be discharged as to the injured party by a breech by the other party:

(a) When one of the parties announces his positive renunciation of the contract, whether this be previous to a partial performance, or after a partial performance. In this case the injured party is entirely relieved from further obligation, or in other words, the contract is discharged. Suit may at once be entered for damages. When the renunciation is only partial, and does not affect a vital portion of the agreement, the contract remains in force, but a suit for damages will lie. The injured party is, however, not bound to treat a formal renunci

ation as a breach of contract, but may insist on performance until the specified time has elapsed.

(b) By one of the parties making it impossible for him to perform his agreement. When this impossibility of performance comes to the knowledge of the other party, he may at once consider the contract discharged, and may enter suit for damages.

(c) By such a failure to perform in case of a "condition precedent'' or failure which goes so to the root of the matter that a recovery of damages would not satisfy the agreement. When the performance of one of the parties is clearly made a "condition precedent" to performance on the part of the other, a failure to substantially perform on the part of the one operates to discharge the contract as to the other.

In engineering contracts a "condition precedent" to the final payment on the part of the owner is usually the certificate of performance to be given by the engineer or architect, he being a third party, and not one of the principals to the agreement. In this case a failure to give such certificate does not operate to discharge the contract between the principals, but does excuse the owner from making a final payment unless it can be shown that the engineer or architect has failed to perform his duties in this respect.

In determining whether or not the failure to perform on the part of the contractor, for instance, is so vital as to operate to discharge the contract entirely as to the owner, and release him from all obligation to pay for the work done, we may distinguish between divisible and entire agreements. A contract or agreement may be considered divisible, when a fulfillment in part is valuable to the other party so far as it goes, and when a failure as to a part does not operate to destroy the value of the partial performance. Thus a contract to build two houses is a divisible contract, would be a satisfactory performance as far as it goes, and a

since the building of one

failure to build the second would not operate to destroy the value of the first; whereas a contract to build a house is an entire contract, since the building would not be serviceable until fully completed.

The degree of failure to perform, as in the case of agreements by contractors and builders, which will operate to discharge a contract on the part of the owner, must be determined by the court or by a jury. In general any substantial failure to perform an indivisible contract will operate to discharge the contract. If, however, the work done or goods delivered are accepted and used, the law will create a new and implied contract on the part of the recipient and beneficiary, by which the party supplying the service or goods can recover a fair price for the same. Such recovery, however, not being under the

contract or in accordance with its terms.

as a rule, discharge

A failure in minor details does not, the contract, but simply furnishes to the other party the right to obtain damages to the extent of the failure. It is very important to note, however, that such failures which give to the injured party only the right to recover damages must be in their nature insignificant, and of small relative importance, not in any sense going to the root of the matter or affecting the value of the parts which have been satisfactorily performed. The law is very severe in enforcing agreements literally and fully, especially where departures have been made intentionally and perhaps against the protest of the other party. In such cases even small failures to comply may be considered as a discharge of the contract. Where the contractor has evidently acted in good faith, much larger failures to perform may be remedied by a payment of damages instead of operating to discharge the entire contract.

When a failure to perform pertains to work which must either be accepted and used, or removed at great expense, as where a structure is built upon the owner's land, if such struct