In Eliason v. Henshaw (1819) 17 U.S. 225, the Supreme Court laid down the rule that, that an offer of a bargain by one person to another, imposes no obligation upon the former, unless it is accepted by the latter, according to the terms in which the offer is made; and that any qualifications of, or departure from, the terms, invalidates the offer, unless the same be agreed to by the person who made it. Until the terms of the agreement have received the assent of both parties, the negotiation is open, and imposes no obligation on either. If it be doubtful whether an agreement has been concluded, or is a mere negotiation, chancery will not decree a specific performance. The Supreme Court of the United States said: "It is an undeniable principle of the law of contracts, that an offer of a bargain by one person to another, imposes no obligation upon the former, until it is accepted by the latter, according to the terms in which the offer was made. Any qualification of, or departure from those terms invalidates the offer, unless the same be agreed to by the person who made it. Until the terms of the agreement have received the assent of both parties, the negotiation is open, and imposes no obligation upon either."