Lacombe, J.,(after stating the fuels as above.) The amendment asked for does not involve an entire change of the character of the action. It is still a suit for the infringement of the same invention as that touching which the evidence already taken was introduced. So much of that ev*797idence as was ’properly taken under-the original bill would be necessary under the bill if amended as complainants pray. It would certainly be very unreasonable do require the parties at great additional expense to take it over again, after both patents are declared upon. No good reason is shown why the court, if it has the power, should not also allow the record to be supplemented by such additional testimony as may bo rendered necessary in consequence of the amendment. An early disposition of the case upon its merits at the least possible expense, and, so far as appears, without doing injustice to either party, would be thus scoured. The authorities cited by counsel show that the granting of the relief now asked for is a matter of discretion, and within the power of this court at this stage of the case. The complainants may amend their hill by the insertion of apt words so that the same shall declare on the omitted patent, (No. 348,072,) and also charge infringement of the invention therein set forth. Upon service of the amended bill defendants may amend their answer as they may be advised, or may plead or demur to the amended bill. Upon the raising of an issue as to the omitted patent the case is re-opened, and additional testimony pertinent to that issue may be taken before a master or examiner. This relief is granted only upon the complainants undertaking to pay the expenses of taking all such additional testimony, (whether introduced by complainants or defendants.) Such expense to include witness fees, mileages, master’s or examiner’s fees, and printing.