The opinion of the court was delivered,

The 1st assignment of error, besides having no merit, is not made according to the rule of the court. It is therefore dismissed without further notice.

The 2d, 3d, 4th, 5th, 6th and 9th errors bring up a single question, to wit: the effect of the agreement of July 21st 1849. We discover no error in the court’s submitting to the jury this agreement as evidence, with the other facts in the ease, that the deeds of July 20th 1849, were but a mortgage of the estates conveyed by these deeds to Matthew S. Richards, of the one-half of the property set forth in the agreement. But we think there was no sufficient evidence to submit to them, that the deeds were only a mortgage of two-thirds of the property. It has been frequently said of late by this court, that the doctrine of a scintilla of evidence is not law, and that a mere spark of evidence jraght not to carry a case to the jury. The evidence must be sufficient to found upon it a reasonable probability of the existence of the fact asserted, and not a mere possibility; and especially when its pur*100pose is to contradict a solemn writing of tbe parties stating the fact otherwise. In this case the agreement of July 21st 1849 sets forth, clearly and without qualification or douht, that the estate to be reconveyed by M. S. Richards to George W. Oakeley was the undivided half part of the 10 acres and 97 perches conveyed by the deeds of July 20th 1849, upon repayment of the sum of $4500 and interest; and that Oakeley, as the actuary and agent of Richards of the mines, vineyards, &c., should pay to Richards, after deducting reasonable costs and expenses, one-half of'the profits for his share. This proportion is corroborated by the conduct of the parties for many years while both lived, in the payment of the interest and the division of the profits. Now there is absolutely nothing in the testimony of Washington Richards, and the memorandum testified to by Mrs. McElroy, to contradict this proportion (the one-half), or to prove that the true proportion was two-thirds to be reconveyed. We are not at liberty to infer from the statement of Judge Richards to Washington Richards; that he was managing the property of Dr. Oakeley, and when the debt was paid, it was to be his property again; that he meant a different proportion from that stated in the written contract. The fact that the deeds conveyed two-thirds of the property to Judge Richards is not alone a sufficient reason to overturn the express terms of the agreement of July\21st 1849. Oakeley was then deeply in debt to Richards and also to others, and unable to pay his creditors. The reasonable interpretation of the entire transaction, is, that the deeds were made to equalize the ownership of the parties, as well as to secure repayment advanced or to be advanced; and therefore that the deeds were absolute as to the one-sixth, thus making Richards’s ownership one-half, and were a security for the repayment of the $4500, upon the one-half left in Oakeley. When parties have thus put their bargain in writing and have acted in accordance with it for so many years, it is error to permit a different interest to be found by a jury on such dubious and uncertain evidence as the statement of Washington Richards. It is undoubtedly true that Judge Richards was managing the property for the benefit of Oakeley, his brother-in-law, together with himself. He never denied this, and the memorandum referred to by Mrs. McElroy, proves no more. But how much of the property or what proportion did he mean ? He gave it no name, and signified nothing contrary to his contract. It is now, after his death, a graceless act in the plaintiffs to ask a jury to infer a mere possibility of two-thirds against the positive agreement of both parties that the security for the money should rest upon one-half only; and against their own interpretation of it for years. Eor this error the judgment must be reversed. The 7th and 8th assignments are not according to rule and will not be noticed.

Judgment reversed, and a venire facias de novo awarded.