— It is a familiar doctrine of a court of equity, that au instrument in writing, intended as a conveyance of lands, wanting in some essential, element to pass the legal estate, — as the attestation of a subscribing witness, or an acknowledgment of execution before an officer having authority to take and certify it, or a defective acknowledgment, — will be regarded as an agreement to convey, and performance of it will be enforced.^-Goodlett v. Hansell, 66 Ala. 151; Jenkins v. Harrison, Ib. 345. It is scarcely necessary to say, that we refer to instruments executed by persons who are sui juris, and not to instruments executed by married women, not conforming to statutes enabling them to convey lands. The court will not decree specific performance of the instrument, unless it is strictly equitable; nor unless it is founded upon a valuable consideration. The instrument stands upon the footing of an executory contract to convey; and if it appears to have been made without consideration, the court will not decree that it be carried into effect. — Hanson v. Michelson, 19 Wisc. 498.
The instrument of which appellant claims performance was intended as a mortgage to secure a debt which is particularly described. The debt forms the consideration which must support it, and, if there be no debt, specific performance of, it can not be decreed justly and equitably. The recital of the debt in the mortgage, and the promissory note embodied in it, are prima facie evidence of the existence of the debt, casting upon the mortgagor the bm-den of disproving its existence and its consideration. An examination of the evidence leads us to the conclusion, that the presumption arising from the recital of the mortgage, and from the making of the promissory note, is *393clearly repelled, and that there was really no debt due or owing from the mortgagor to the mortgagee when the instrument was executed. The antecedent debt to Ephraim Oates, the assignor of the mortgagee, which forms a large part of the amount for which the note was given to the mortgagee, is shown to have been fully paid before the note was assigned. If there was any other consideration for the note, the mortgagee must have known of what it consisted, and had the power of proving it. The evidence of the mortgagor is clear and pointed, that there was no other consideration, and that he had no transaction with the mortgagee, from which a debt could originate. "When a party, having the means and opportunity to prove a fact, fails or neglects to offer evidence of it, the presumption is fair and just that it does not exist.
We do not regard it as necessary to consider any other question the case is supposed to present, for upon this clear ground, that there is no consideration for the instrument, specific performance of it was properly refused. Let the decree 'be affirmed.