The nonsuit in the other case was set aside upon the ground of surprise. In the principal case a trial has been had, in which the defendant chose to rely upon the weakness of his adversary's title, without producing one of his own. No application was made for a continuance upon the ground of the want of a grant. Where the party voluntarily comes to trial we cannot permit him first to try one method of defence and then another; this would be trifling with the time of a court of justice, and prostrating the most important institution for determining the disputes of men — the trial by jury. It would be too dangerous to allow parties to feel the public pulse through the medium of a jury, and make experiments upon the different points arising in their causes; besides, it is to be presumed that the defendant knew where his grant was before the trial. He certainly must have known whether he should rest his case upon a title or not. If he knew of the evidence, and did *Page 121 not produce it, he cannot afterwards make it the cause for a new trial.
With respect to the discovery of King's testimony, we are of opinion it is not sufficient to set aside this verdict; it is to impeach Walling's credit which was attempted at the trial, but we are clearly convinced without effect; there was testimony confirming his evidence. Walling swore that he was not interested; by the principles of law we are constrained to presume that what he swore was the truth. One attack having been made on his credit upon as strong ground as that made in the affidavit, as it occurs to us, which had no effect either with the jury or the court, we do not think ourselves authorized to grant a new trial upon this ground.2 Rule discharged.
