The appellant’s sole contention is that the trial judge erred in denying his mid-trial motion for a continuance. The critical facts are that the motion does not comply with F.R.Civ.P. 17(b); the purpose of the motion was to offer testimony impeaching a Government witness on an immaterial point; and, during the trial, the appellant offered no testimony. We hold that the trial court was well within sound judicial discretion in denying the motion. The judgment is affirmed.