"It is not disputed that, generally, to a bill for a specific performance of a contract for sale, the parties to the contract only are the proper parties; and, when the ground of the jurisdiction of Courts of Equity in suits of that kind is considered it could not properly be otherwise. The Court assumes jurisdiction in such cases, because a Court of law, giving damages only for the non-performance of the contract, in many cases does not afford an adequate remedy. But, in equity, as well as in law, the contract constitutes the right and regulates the liabilities of the parties; and the object of both proceedings is to place the party complaining as nearly as possible in the same situation as the defendant had agreed that he should be placed in. It is obvious that persons, strangers to the contract, and, therefore, neither entitled to the right, nor subject to the liabilities which arise out of it, are as much strangers to a proceeding to enforce the execution of it as they are to a proceeding to recover damages for the breach of it."[Emphasis supplied ]'”