The right of the plaintiff to recover depended on his ability to prove an existing debt due by the garnishee.

Having attempted to do so by proving a specific contract, he-was clearly estopped from denying the validity of that contract. Had he succeeded in proving it to be invalid, he would have-; proved that the debt did not exist.

' There is no presumption of fraud in the fact that the defendant paid the instalments before they became due, and was allowed a rebate of the interest on the sums thus paid.

Judgment affirmed.