Bigelow, C. J.
We see no reason for doubting the correctness of the conclusions to which we came concerning the rights of the parties to this suit as stated in 12 Allen, 459. The course of the second trial and the instructions of the presiding judge in submitting the case to the consideration of the jury seem to have been substantially in conformity to the rules and principles by which we have held that the use of the water of the spring in controversy as between these parties is to be regulated and governed.
But a new question appears to have arisen out of the facts proved at the last trial. The evidence tended to show that the waters of a natural stream or brook had been diverted from, their original channel at the time the reservoir was built for the purpose of holding and keeping pure the waters of the spring. It was also proved that the waters of this brook, before such diversion, when flowing in their natural course occasionally ran into the spring. The defendant also offered to show that prior to the time when this action was brought he restored the waters of the brook to their original channel where they passed through his *28own land. In this state of the evidence, the defendant asked that the jury might be instructed that he could not be held liable for damages caused by impurities in the waters of the spring, which arose from the waters of the brook while flowing in their natural course, and that he had a right to restore the brook to its original channel on his own land, notwithstanding some impurities might in consequence thereof pass into the reservoir. This instruction was refused. But it seems to us to be very clear that it ought to have been given. The plaintiff had acquired no right as against the defendant to continue the diversion of the ancient stream, nor had he any such title to maintain his reservoir in the condition in which it was put by a previous owner of the spring as would warrant him in restraining the defendant from restoring the original course of the stream within the limits of his own land. Upon the report of the evidence on the exceptions, we cannot see that this omission to instruct the jury may not have operated seriously to the prejudice of the defendant. One of the causes of action set forth in the declaration is for defiling the waters of the spring. This may have been caused in part at least by the overflow of the stream in consequence of the acts of the defendant in restoring, as he had a right to do, the waters of the brook to their ancient course. By the refusal of the court to give the instructions for which the defendant asked, the jury may have been led to include in their estimate of damages the defilement of the waters of the spring occasioned by the lawful acts of the deféndant done upon his own premises. For this reason, we think the order must be
Exceptions sustained.