 Other contractual letters (such as one revoking the offer) do not take effect until the letter is delivered, as in "Stevenson, Jacques & Co v McLean" (1880) 5 QBD 346.The implication of this is that it is possible for a letter of acceptance to be posted after a letter of revocation of the offer has been posted but before it is delivered, and acceptance will be complete at the time that the letter of acceptance was posted—the offeror's revocation would be inoperative.Example 1