This case comes before the court on a demurrer to a supplemental bill. Several causes were assigned, out they mainly resolv» themselves into two, namely :
*781. That this supplemental bill was irregularly filed, being done without leave of the court first obtained for the purpose; and
2. That it does not appear, either by the bill itself, or by any affidavit or other evidence in support of it, that the matter se: forth in the supplemental bill has been newly discovered, or that it could not have been introduced originally, or by way of amendment, into the original bill.
The practice of chancery, in all its various details, is still so comparatively new in this court, and the court are so frequently called upon to examine and apply the rules to new cases as they occur, amidst the pressure of common law engagements, that we are obliged to proceed with caution, and are in danger of falling into some irregularity. '
From the short examination which we have been able to give the subject, being disposed to speed the cause by an early decision, it appears to be an established rule, and on the whole a useful one, that a supplemental bill ought not to be filed as a matter of course, but only by leave of the court first obtained ; and that upon sufficient cause shown. The filing of a supplemental bill after the cause is at issue, and publication of the evidence passed, might lead to great delay and abuse, and operate as a means of evading many of the salutary rules requiring the parties to set forth their full grounds, and procure all the evidence they respectively rely upon, before publication.
In order to lay the foundation for filing a supplemental bill, it ought to be shown to the satisfaction of the court, either
1. That the matter, relied upon as supplemental, has arisen since the commencement of the original suit; or
2. That the facts relied on have first come to the plaintiff’s knowledge, or been made known to him in such a manner that. he could avail himself of them, since the cause has passed the stage in which he might have had leave to amend; or
3. That the plaintiff has been prevented, through inadvertence, misapprehension on the part of himself, or his agents or counsel, or by some other cause satisfactorily shown, from availing himself of the matter proposed to be introduced by his supplemental bill, at an earlier stage of the cause.
*79The supplemental bill must be confined to such matter, and must be verified by affidavit or other satisfactory proof.
Whether, in case of a supplemental bill filed without leave of court, the objection should be taken advantage of by demurrer or motion to dismiss, is a question which it is not necessary to decide ; because the plaintiff has moved for leave to file such a bill, and the court are of opinion that it is not too late, if sufficient cause is shown, to sustain it. The case will therefore stand open upon that, motion.