3. Interest, § 56*—how should be computed upon breach of contract. In an action to recover on a contract whereby defendant agreed that plaintiff should have the exclusive right to sell its cars within a named territory, and should have as his compensation an agreed discount on defendant’s listed price for cars sold by plaintiff, and where judgment for plaintiff included the amount of such discount on the price obtained for a car sold by defendant within such territory in breach of the contract, held that interest should be computed on the amount of the discount from the date of such sale.4. Interest, § 81*—when error exists in computation of interest. In an action to recover on a contract whereby defendant agreed that plaintiff should have the sole right to sell its motor cars within a named district, a judgment for plaintiff of $1,921.83, held excessive to the extent of $63.17.