The question which the defendant desired to ask did not relate to errors in the account in controversy, but in other accounts. Its purpose was to test the correctness of the bookkeeper. When a book account is proved, and the accuracy of the bookkeeper is involved, it is not error of law to allow other accounts in the same book to be introduced in impeachment of his accuracy: but how much time will be profitably and properly spent on the collateral inquiry is a question of fact to be determined at the trial term.

The request for instructions was properly denied.

Judgment on the verdict.

SMITH, J., did not sit: the others concurred.