delivered the opinion of the court, October 30th 1876.
Perhaps no rule of law is better settled than that a tenant in possession under a lease shall not be allowed to dispute the title of his lessor. Yet this rule, like most others, has its exceptions. Where the tenant has been induced to accept the lease by misrepresentation, fraud or trick practised upon him by the lessor, he is not estopped from setting up a superior title to. that of the lessor: Hamilton v. Marsden, 6 Binn. 45; Brown v. Dysinger, 1 Rawle 408; Baskin v. Seechrist, 6 Barr 154. It was said by Justice Bell in the last-named case, that “ It matters not whether the deception practised originated in voluntary falsehood or in simple mistake, for the immunity it confers springs not so much from the. fraud of the usurper as from the wrong which the deception would otherwise work upon the rights of the lessee.” Here it is clear that both parties to the lease believed the well to be on the four acres described therein. The master so finds. We have then the case of a mutual, mistake. It turns out that the well is upon the property of another person, who claims the rent or royalty for its use. The lessors have filed their bill in equity for an account of the oil taken from the well, the royalty for which they claim under the terms of the lease. The master finds the fact that the defendants (lessees) have offered, since the bringing of the suit, to surrender possession to the plaintiffs (lessors) of the demised premises. The court below made a decree in favor of the complainants, to which decree this appeal was taken.
We do not propose to indicate how far the matters alleged by the, lessees would avail them as a defence in a proceeding at law to recover the rent under the lease. This is not such a proceeding. The lessors have invoked the aid of a court of equity. We think they have chosen the wrong tribunal. The rule that a tenant in possession cannot dispute his landlord’s title is not more firmly established than is the familiar principle of equity that when a contract is made under a mistake, or in ignorance of a material fact, Tfhich is of the very essence of the contract, it is voidable and relievable in equity: Miles v. Stevens, 3 Barr 21; Gibson v. The Union Rolling Mill Co., 3 Watts 32; Horbach v. Gray, 8 Id. 492; *465Geiger v. Cook, 3 W. & S. 266; Jenks v. Fritz, 7 Id. 201. We have here a mutual mistake upon a matter that was of the very essence of the contract. It is in just such cases that equity relieves against the hard rules of the common law. But, as before observed, it is the lessors who are seeking the aid of equity to enforce their contract, notwithstanding the existence of this admitted mutual error affecting the life of the contract itself. They appeal to the conscience of a chancellor to make an unconscionable decree. For, if we make the decree prayed for, it would not protect the lessees from a suit from the owner of the well for the royalty, and they would be without remedy. It needs no argument to show that these complainants have no equity. We leave them to their remedy at law.
The decree is reversed and set aside, and the bill dismissed. • The costs to be paid by the appellees.