"The speculative question has lately been asked at what point of time acceptance by an act is complete, and it is suggested that A. may request B. to do something, say to move a piece of furniture, for reward which A. names, that B. may do a substantial part of the work, and A. may revoke his offer at any time before the work is complete, leaving B. without a remedy, or at least any remedy on a contract. But surely the acceptance is complete as soon as B. has made an unequivocal beginning of the performance requested, a commencement d'execution, to use the term familiar in French law. Whether anything is payable before the whole of the work is done depends on the terms express or implied of A.'s offer on which B. acts. As a matter of fact A.'s offer will almost always be a conditional offer, and will become, on acceptance, a promise conditional on the work being done within a reasonable time and otherwise competently. Such a conditional promise is still a promise, and wholly different from a revocable offer." 29 On just what theory the beginning of performance is an acceptance is not explained. Of course if we were discussing a case where the offer expressly called for a counter-promise as an acceptance, or was open to the inference that a counter-promise was called for, without indicating the mode of expressing the counterpromise, the beginning of performance might well be taken as the expression, or manifestation, of such promise. In that case we would be dealing with an offer contemplating a bilateral contract. By hypothesis we are concerned with a case where such an inference is excluded, the case of an offer actually contemplating a unilateral contract. In case of doubt the courts interpret an offer as contemplating a bilateral contract. That seems to be what is meant in Offord v. Davies, supra, by the remark of Erle, C. J.: "But the moment the coach builder has prepared the materials, he would probably be found by the jury to have contracted." This, too, is the process of reasoning adopted by Justice Holmes in Martin v. Meles.30 Yet offers contemplating unilateral contracts are in fact made, and the question remains, are such offers ordinarily revocable after performance has begun? For though we discard Pollock's idea that beginning performance is acceptance, is there not truth in Judge Preston's suggestion that the commencement of perform ance renders the offer irrevocable? Let us assume a concrete case: A. says to B., "I have had enough of your promises in the past and want no promise from you, but if you will put my sugar-house machinery in good repair I will pay you $100 for the job, and if you will begin immediately I will give you a reasonable time to complete the work." Are there not two offers here - one, the principal offer of $100 for the repair of the machinery; another, or collateral, offer to keep the principal offer open for a reasonable time if the offeree begins work at once? The principal offer contemplates acceptance by the act of repairing the machinery, and no contract will result from it until the machinery is fully repaired. The collateral offer also contemplates a unilateral contract, the acceptance to be beginning the work at once. If the work is begun at once there is a contract to keep the principal offer open for a reasonable time. By beginning immediately the offeree has "paid-for" the offer. So if the principal offer had fixed a definite time for completing the work, the commencement of the work would be the acceptance of, and consideration for, the implied promise to keep the principal offer open for the time so fixed in it. The offeree is thus protected by a contract to keep the offer open. Should the offerer thereafter attempt to withdraw the offer, this repudiation of his contractual obligation would give the offeree an action for damages, and it may be that in exceptional cases the offeree may ignore the repudiation, complete the performance and hold the offerer to the resulting contract. The analysis above suggested fully accords with the intentions of the parties, as it must in order to be admissible; whether the implied contract exists depends wholly upon the intentions of the parties. That ordinarily in this sort of dealings such an implied contract is contemplated is shown by the fact that by it alone will both parties be secured the intended positions. The offerer incurs no liability on his principal offer until the work is done, not because it is a condition in a contract already made that the doing of the work is to precede payment a bilateral contract could be made to serve equally well for that—but because the principal offer, viz., to pay for the work, will not ripen into a contract at all until the whole work is done: the offerer has only given the offeree an option to reject the principal offer or accept it by completing the act or acts called for, within the time limit. Thus the suggested analysis nowise interferes with securing to the offerer absence from liability except upon punctual and otherwise precise performance by the offeree, the principal object in mind when an offer contemplating a unilateral contract is made. The offerer, as Professor Williston says, can impose such conditions as he pleases; he may make the time for acceptance impossibly short if that is his whim, or make the task ever so difficult in other respects, and no liability beyond what may result from a repudiation of the collateral contract can possibly arise unless the task is completed within the time and in strict compliance with all other conditions. On the other hand, the offeree is secured the intended position. By commencing the work he is not bound to complete it. The principal offer contemplates a unilateral contract. By commencing the work the offeree has only accepted the collateral offer and paid for the option of accepting or rejecting the principal offer. He is secured the very opportunity which in such cases it is normally expected he shall have, i. e., an opportunity to see whether he can accomplish the work within the allotted time and entitle himself to the contemplated compensation. In short, the analysis here suggested does not vary the position of the parties from that depicted above in the quotation from Professor Williston, with the single exception that the revocation of the offer does not leave the offeree devoid of remedy. In the case above put, the inference that the principal offer carries with it the implied offer to keep the former open if the work is begun within a reasonable time is made easy by the explicitness of the language used, but does not the inference come clearly in less explicit cases? Take the facts of Biggers v. Owen, an offer of reward for delivery to the sheriff with evidence to convict. Does not the offerer fairly say that if you produce substantial results within a reasonable time, I will give you a further reasonable time to complete? In the case of offers made to the public, i. e., to an indeterminate person, if X. alone makes a substantial beginning the option created would work in his behalf only, and the offer could still be withdrawn as to all others. The inference is stronger in the sugar-house case because from the beginning of the work the offerer is presumably being enriched. The inference of the collateral offer is purely one of fact, however, and the existence of a benefit is not a sine qua non. The inference can properly be drawn whenever and only when the proposition made would reasonably be taken to offer a reasonable or a stated time for performance in exchange for the commencement of it within a stated or reasonable time. Any express or implied reservation of a right to revoke at any time will negative the inference of the implied accessory contract. If the offer reasonably construed proposes no such contract there is no justice in enforcing one against the offerer because some abnormal person has been misguided by it. An offerer is still free to impose such terms as he pleases, and he can make an offer contemplating a unilateral contract without annexing an option to it. The difficulty with the current conception is that it takes too harsh a view of the ordinary offerer, attributing to his proposal a more selfish meaning than it bears when reasonably construed, and a meaning which comes as a shock to a normal offeree, in ordinary cases. Suppose a promise of a sum of money is made in consideration that the offeree refrain from a bad habit for five years. First the court must consider whether the offer contemplates a bilateral contract. Was it meant that the offeree should promise, either by word or act, binding himself to refrain? If not, the offer contemplates a unilateral contract; that is, that there is to be no contract to pay the money until the act called for is done. What act? Refraining for the whole period. Was the offeree to get nothing if he refrained only two years? Obviously he was to get nothing. But does that lead us to the other extreme, that if he does refrain for two years and is still refraining, the offer may be withdrawn without liability? Surely that was not in the contemplation of the parties. As Professor Ashley says, it is a lame thing to tell the offeree now that he should have made a bilateral contract. That is what the parties did not want. The offerer did not seek to bind the offeree, but to leave him free to accept or reject. The offerer, on his part, wanted only to be free, until the offeree did what he called for, from any contractual obligation to pay the money. On the other hand, it was contemplated that the offeree should have the opportunity to do it, and thereby create a contract. The fair inference is that an implied proposal was made to keep the offer open for the designated time in consideration that the offeree commenced to refrain. Apart from the above interpretation by which an implied promise to keep the offer open is found in some cases, there may be question as to the consideration for this promise, but surely not a serious one. The finding of the consideration, for keeping the offer open, in the act of beginning performance is soundly in accord with the doctrine of consideration if the offer reasonably bears the interpretation above put upon it. Any future act which the offeree is not otherwise legally bound to do may be consideration for a promise, whatever that act may be, if it is the act called for in exchange for the promise, i. e., called for either expressly or inferentially in the light of a reasonable construction. It has been held that a public notice that an auction is to be without reserve is an offer which is capable of acceptance by the acts of attending and bidding the highest, and while if the auctioneer refuses to knock down the goods there is no contract to sell 31 there is a contract with the auctioneer of which he commits a breach by refusing to knock them down.32 In short, Warlow v. Harrison holds that the announcement of an auction sale without reserve is equivalent to a proposal, that if you attend the sale and bid the highest, I, the auctioneer, agree to accept your offer. That is, the mere acts of attending and bidding highest are the acceptance and consideration for the auctioneer's promise. This is true only if the auction notice may reasonably be construed to contemplate those acts in that light. So it has been held that a public announcement of train schedules is a promise-offer to run trains at the times scheduled, contemplating as acceptance and consideration the mere act of entering the station with intention of becoming a passenger, though no ticket has yet been bought.33 This decision goes further than the American case of Sears v. Eastern R. R. Co.,34 which holds that the purchase of a ticket is an acceptance of an offer to run the train at |