Sec 18

That a proposal made by me to another, in writing or through a messenger, does not bind me until I know it is accepted, may be conceded in all cases in which the proposal, either from its express terms or from the course of business to which its interpretation is subject, is dependent for its binding force on notification to me of its acceptance. We may also hold that generally a posting of a letter is not delivery to the sendee.1 On the other hand it is competent for me to bind myself by a proposal conditioned upon the acceptance being forwarded to me by mail.-It is no objection to this position that by it one party is conditionally bound and the other not. This objection if good would vitiate all conditional sales and sales on trial; yet conditional sales and sales on trial, as we will see elsewhere, have in many instances been held good.2 The proposal is simply this: "If you will post an acceptance to this offer within a fixed time, or a reasonable time, as the case may be, I will forward you the goods, or perform for you the service." On posting the answer by the party addressed, the proposer becomes bound on his proposal, though the answer never reached him. Even supposing the loss occur through the negligence of the post-office, and not his own negligence, yet, on such a proposal, the loss falls on him who designated this channel of communication, or did business in subjection to a usage by which it is designated, more properly than upon the party forwarding the acceptance.3 This reasoning applies more strongly to cases of acceptance by telegraph (supposing that be the mode of acceptance designated or sanctioned by practice), since there is recourse over to the telegraph company in case by its negligence the acceptance is not communicated.4 It is on the assumption that in proposals communicated in the ordinary course of business there is an implied agreement to be bound by an acceptance if forwarded promptly by post or telegraph, that we can sustain the numerous rulings in England and the United States, that an acceptance, whether posted or telegraphed, takes effect from the time when it is forwarded.1 If it be said that there is no consideration, the answer is that the proposal is: "I will be bound if you will put aside other openings and take this." The consideration is the detriment to the promisee of putting aside other openings.2 But an acceptance by post, to bind, must be held in the hands of an agent to whom it was entrusted by the accepting party, such agent not being the agent also of the proposer.1 - By the Indian Contract Act, "the communication of an acceptance is complete as against the proposer when it is put in-a course of transmission to him, so as to be out of the power of the acceptor; as against the acceptor, when it comes to the knowledge of the proposer. The communication of a revocation is complete as against the person who makes it when it is put into a course of transmission to the person to whom it is made, so as to be out of the power of the person who makes it; as against the person to whom it is merit the letter accepting the offer is posted." He further said: "I am aware that Pothier and some other writers of celebrity, are of opinion that there can be no contract if an offer is withdrawn before it is accepted, although the withdrawal is not communicated to the person to whom the offer has been made. . . . Against this view, however, it has been urged that a state of mind not notified cannot be regarded in dealings between man and man ; and that an uncommunicated revocation is, for all practical purposes, and in point of law, no revocation at all. This is the view taken in the United States. . . . This view appears to me much more in accordance with the general principles of English law than the view maintained by Pothier. I pass, therefore, to the next question, namely, whether posting the letter of revocation was a sufficient communication of it to the plaintiff. The offer was posted on the 1st of October, the withdrawal was posted on the 8th, and did not reach the plaintiff until after he had posted his letter of the 11th accepting the offer. It may be taken now as settled, that where the offer is made and accepted by letter sent through the post, the contract is completed the moment the letter accepting it is posted. . . . When, however, these authorities are looked at, it will be seen that they are based on the principle, that the writer of the offer has expressly or impliedly assented to treat an answer to him duly posted as a sufficient acceptance and notification to himself; or, in other words, he has made the post office his agent to receive the acceptance and notification of it. But this principle appears to me to be inapplicable to the case of the withdrawal of an offer. In this particular case I find no evidence of any authority in fact given by the plaintiff to the defendants to notify a withdrawal of their offer by merely posting a letter ; and there is no legal principle that compels me to hold, contrary to the fact, that the letter of the 8th of October is to be treated as a communication to the plaintiff on that day, or on any day before the 20th, when the letter reached him." See article in Journal of Jurisprudence and Scottish Law Mag. for July, 1880, cited Benj. on Sales, 3d Am. ed. sec 69.

Agreement to bebound on mere posting of acceptance may be implied.

1 Newcombe v. De Roos, 2 E. & E. 271 ; British Tel. Co. v. Colson, L. R. 6 Ex. 118.

2 Supra, sec 16 ; infra, sec 545 et seq.

3 Hallock v. Ins. Co., 2 Dntcher, 268.

4 See infra, sec 27, for cases. That promises dependent on contingent action of third parties bind, see infra, sec 593.

1 See remarks of Braniwell, J., Brit. Tel. Co. v. Colson, L. R. 6 Ex. 118; Mellish, J., Harris's case, L. R. 7 Ch. 594; and Blackburn, L. J., in Brogden v. R. R., L. R. 2 App. Ca. 691; Vassar v. Camp, 1 Kern. 441; Trevor v. Wood, 36 N. Y. 307 ; Howard v. Darley, 61 N. Y. 362 ; Hallock v. Ins. Co., 2 Dutcher, 268, and cases cited infra.