Provided always, that such verdict or determination shall not be prevented or delayed by the absence or non-attendance of any person interested in such thirlage, but that the jury shall proceed on such evidence as shall be produced to them by any of the parties then and there attending, and pronounce such verdict and determination as aforesaid, which shall be as valid and effectual to all intents and purposes as if all the parties interested therein had attended and been heard in relation thereto; but it is also provided, that if any of the parties shall shew sufficient reason for adjourning the said day appointed for taking the verdict of the jury, it shall be lawful for the said sheriff or steward depute or substitute to make such adjournment to any day within thirty days from the day first appointed, the party praying an adjournment always defraying all expences thereby incurred.