Woods, J.
The first question arises upon the ruling of the court, that the parties might fix a limit to their respective claims, different from that which might be considered the true con*301struction of the deed from the plaintiff to Ely, Earr, and Redington. This ruling was made upon objection to the competency of parol proof of an agreement by the parties, upon a monument, to which the defendants might raise their dam, and which would give the grantees a right to raise the water higher than they could have done by the deed. The question is, whether the ruling, admitting the evidence, was correct. The agreement was, in effect, that the water might be raised upon the premises and works of the plaintiff, to any height to which a dam of given elevation would raise it in any and every state of the water; although it would thus be raised higher, and would flow the lands and works of the plaintiff to a greater extent than was contemplated by the grant. The effect of the proof of the agreement, if it can have effect at all, is to enlarge the grant, in fact, by a parol agreement. The ruling admitted the evidence, notwithstanding it must have that effect. And the question is, whether a parol agreement can have effect as a contract enlarging the rights of the parties, or as conclusive evidence of the existing rights, and of the extent of the existing claims of the parties. It is believed that no case can be found, giving any countenance to the idea that a parol agreement can be allowed to have the effect, directly, to enlarge a grant which is required to be made by deed. If such agreement can affect the grant at all, it must be as matter of evidence of the extent of the respective rights of the parties under the deed, which is conclusive, and the contrary whereof cannot be shown by other proofs. That parolagreements have been allowed to have that effect in regard to divisional lines of the lands of adjoining owners in this State, where an agreement has been made, and in conformity therewith, such adjoining owners have erected monuments upon the line, and have gone into actual occupation of the lands on both sides, or where, as it is termed, the agreement has been'executed, is not to be denied. Sawyer v. Felton, 6 N. H. Rep. 107; Gray v. Berry, 9 N. H. Rep. 473. The same doctrine is holden in a similar case in Pennsylvania. Ebert v. Wood, 1 Binney, 215. A similar principle is established by the supreme court of New York. Clark v. Wethey, 19 Wend. 320. *302It seems, however, that the courts of New York are not inclined to extend the principle, but to limit it, as in the ease referred to. Rockwell v. Adams, 16 Wend. 285. But, in the States of Maine and Massachusetts a different doctrine prevails. It has been decided that such agreement, and actual location of a line between owners of adjoining lands, are strong evidence of the accuracy of the line thus established, although not conclusive so as to prevent either party from showing that it was settled erroneously. Gove v. Richardson, 4 Greenl. 327; Whitney v. Holmes, 15 Mass. 153. The decisions, then, upon this point, are not agreed; and "upon examining them, and the reasons assigned for them, we are not inclined to extend the principle established in this State beyond the cases in which it has already been applied, and certainly not to cases where there is no ambiguity in the terms of the deed, and no difficulty or doubt as to the extent of the rights of the parties under the deed.
Where the terms of the deed are not ambiguous, and the extent of the rights of the parties, under the deed, are plain and evident, to hold that a parol agreement shall in fact enlarge the rights of either party beyond those given by the deed, under the name of conclusive evidence, is nothing more or less than to give such parol agreement the effect of a grant of real estate. A doctrine having any such effect, is in direct contravention of the' statute of frauds, and cannot be sustained. That an agreement of the parties should have the effect of evidence, even of strong evidence, of the accuracy of the line agreed upon between adjoining, owners, is an admissible doctrine; but that it should have the effect, when founded in error in fact, and it is so shown, to enlarge a grant required to be by deed or other writing, is a doctrine which does not approve itself to the judgment by force of any very obvious and controlling reason, or any inherent principle of justice upon which it is seen to rest. We are not, then, prepared to carry the doctrine of the cases referred to, in this State, beyond the cases in which it has been applied, or cases in which the reason for the doctrine is seen .to be at least equally cogent and convincing.
The case under consideration is not one of an agreement upon *303a divisional line between lands of adjoining owners. The deed does not look to any particular divisional line, or to the establishment of any such line, as forming the limit of the grant, or of the rights of the parties under the grant. But it looks to the practical operation of the water by means of a dam, to be erected by the defendants upon lands of their own, upon the machinery at the mills of the plaintiff, at his mill-dam above the contemplated dam of the defendants, as limiting and determining the extent of the grant and the rights of the parties under it. And it looks, also, to such operation, for that purpose, in all the varying states of the water contemplated by the deed. If any other reason were necessary to be assigned why the doctrine contended for should not be applied to a case like the present, than that it allows of the enlargement of a grant by parol, in contravention of the statute, it will be found, we think, in the fact that the principle must be applied in all cases, and between all parties alike; while at the same time, although it may be that persons learned and skilled in the science of hydraulics might, upon an investigation and a scientific calculation, determine, with some degree of certainty, the height of a dam, by means of which the operation of the water upon the machinery would not be injurious, still, the requisite degree of skill would not be found to exist in any but a very limited portion of such persons as are likely to be parties to conveyances of water-rights, such as are in- controversy in the present case. Much wrong and injustice would therefore be likely to be accomplished by the application of such a doctrine to such a case ; and much more, we think, than by denying its application. And besides, the denial has the advantage of being sustained by principle, and of being in conformity with the provisions of the law.
The right granted is a right to raise the water ; but not so as to interfere with the operation of the machinery of the plaintiff at the mill above, except in extremely high water in times of freshet. The right claimed under the agreement, is a right so to raise the water as to interfere with the operation of the machinery, and beyond the grant. And it is conceded to be so. An agreement, in any ease, to affect the rights of the parties, even as to *304divisional lines, must be intended to be an agreement fixing upon tbe actual, true line, and not intended to change or enlarge the grant. This position is conceded in all the cases.
In the cases in which the doctrine contended for by the defendants prevails, of course an agreement in fact founded in mutual error, is held conclusive evidence that there is no error; or the parties having made the agreement, the error cannot be shown, and thus the grant is in effect enlarged or altered, but not eo nomine. If such a doctrine is to prevail in the case of divisional lines of lands, in cases in relation to which parties may be fairly supposed to have competent knowledge to act understandingly, or the means of such knowledge, enabling them to act with a reasonable degree of certainty, we think it should not prevail in cases like the present, where it would be most difficult to determine the operation of the water in all its stages, except by actual experiment. Unskilled men would be almost certain to commit errors in such cases. And this would not be the result of any uncertainty or ambiguity in the terms of the grant, or deed, which could be aided by evidence, but only of the difficulty of determining the operation of the water except by experiment. And it is apparent that, without actual trial, or without unusual skill on the part of the parties, any such agreement would be scarcely more than a mere expression of opinion upon the subject. And we think it would be going quite too far to hold, that such expression of opinion, in a matter of so much uncertainty as to the fact, is conclusive evidence of the fact, beyond all control of other evidence showing it to be founded in mere error. If, when parties have acquired rights in real estate by virtue of deeds, it is desirable that they should be enlarged or altered, it is enough that the matter is open for further negotiation; and if it be intended to enlarge, or in any way alter the rights required, it may be done by deed. 17 Maine Rep. 128. When that is required by the law and the decisions of the courts, then all is done that can be done to guard persons, sometimes ignorant, and sometimes injudicious, against the injurious consequences of their own follies or weaknesses. And such, in addition to necessary errors of understanding, the un*305certainty of memory, and, more than all, the danger of falsehood, was the reason for the enactments requiring all conveyances of real estate to be in writing, and attended, in certain cases, and for some purposes, with the formalities of a seal and witnesses.
It is going far enough, we think, to hold, in a case like the present, that an agreement is evidence to be weighed by a jury in determining whether the parties have exercised rights beyond those granted by the deed when construed by the court; but that it is going quite too far, to hold that such an agreement is conclusive evidence that the right claimed according to parol agreement is the just right granted by the deed, when it is shown by evidence, and is made to appear that it is not, in fact, in accordance with the deed.
It may well be conceded, in the present case, that there was sufficient evidence of a license originally given in 1835 to Ely, Parr, and G-. B. Bedington, to raise the water to the under side of the “ stream mud-sill ” at the plaintiff’s mills, by means of a dam to be erected upon the land conveyed to them by the plaintiff ; and it may be assumed upon the case that the water was not raised to a greater height than the license, if continued, would justify. But a question arising upon the ruling of the court is, whether, upon the facts reported, the license can be holden to be assignable, and to protect H. C. Bedington until notice should be given him to remove the nuisance.
We regard it as well settled, upon the authorities, that a license to be exercised upon land is a personal trust and confidence, and is not assignable; and that although it may be binding as between the parties, it will not pass to a purchaser. Mr. Chancellor Kent says, such “ license is founded on personal confidence, and is not assignable nor within the statute of frauds.” 3 Kent’s Com. (2d ed.) 452, and cases cited in note (a). In Stevens v. Stevens, 11 Met. Rep. 255, Mr. Justice Wilde says, “ a distinction is made in some of the cases between a personal privilege which is not assignable, and an easement carrying an interest in land.” This is an evident recognition of the principle that a license is not assignable; and, from its very nature, being a *306mere permission to one to do an act, it cannot be construed as conferring an authority upon others to do such act, or exercise the same license. Harris v. Gillingham, 6 N. H. Rep. 11, recognizes the doctrine, that a sale and conveyance of the land upon which the license is to be exercised will operate a revocation of the license, and discharge the land thereof. So, also, of a sale of the erection upon the land made in virtue of the license, that the purchaser acquires no right to occupy it upon the land, but only a right to remove it. So when G., by writing under hand and seal, gave to H. the privilege, during pleasure, to occupy a certain piece of land, and H. afterwards sold the land to 0., it was holden that the instrument given by G. was a mere license or personal privilege to occupy, which was determined as soon as H. undertook to convey the premises. Jackson v. Babcock, 4 Johns. 418. In Ruggles v. Lesure, 24 Pick. 187, the court-say, “licenses are personal, and terminate with the death of either party.” A similar principle is recognized in Seidensparger v. Spear, 17 Maine Rep. 123; Ex parte Coburn, 1 Cowen, 368 ; Sheppard’s Touchstone, 231. It would seem quite clear, then, that the conveyance to H. C. Redington by Ely and G. B. Redington of June 24, 1840, gave him no interest or benefit in the license, and, consequently,'could not, of itself, be held to furnish him any ground of defence in this action. In fact, such a license to a person is nothing more than an authority to do a particular act or series of acts upon the land of another, without giving him any estate therein, or authority to license others to do or exercise the same right; and being holden to be founded in personal confidence and not assignable, it is quite apparent that H. C. Redington stands, in relation to the transaction which forms the foundation of this action, as if no such license had been given to Ely, Farr, and G. B. Redington, as is supposed. - And so far as the license is concerned, we think it quite immaterial whether H. C. Redington had notice of the existence of the alleged nuisance or not. It could affect him in this respéct neither injuriously nor beneficially. If the license did not pass to him, it is difficult to see how a want of notice could give it effect so as to enable H. C. Redington to shield himself under its authority. And we think it is entirely clear that it could not.
*307It is further contended, on the part of the plaintiff, that the darn having settled and become ruinous, and the factory having been burnt, the defendants could not, without a new license, add to the height of the dam so as to raise the water as high as it was originally; that the license was merely a license to erect a dam of a particular height, but not to repair or restore it; and terminated with the decay of the dam. And the authorities would seem to show, that a license to erect a dam will give no right to repair and restore the dam when it has become ruinous and decayed, but is thereby determined. Mr. Chancellor Kent says, “ If a parol license be granted for a temporary purpose, as the permission to erect a dam, it has been held to terminate with the decay of the dam ; .as the purpose of the dam has been fulfilled.” 8 Kent’s Com. 451, and the cases there cited. The language of the court in Cook v. Stearns, 11 Mass. 533, seems strongly to countenance the doctrine, that a license to build a dam does not authorize the repair of it or its reerection. “If,” say the court, “ the defendant had a license from the former owners of the plaintiff’s close, to make the bank, dam, and canal in their land, this extended only to the act done, but did not carry with it an authority, at any other time, to enter upon the land.” The doctrine stated by Mr. Justice TTpham in Ameriscoggin Bridge v. Bragg, 11 N. H. Rep. 102, is thus: “A license to erect a bridge for the taking of toll is clearly distinguishable from a mere consent of passing and repassing, and we think when it is once executed, it is either irrevocable while the bridge continues, or, if revocable at all, only so on full compensation of all expenditures made, and damages occasioned by such revocation. Such a license may undoubtedly terminate by the decay of any erection under it, and it would have terminated in this case, or might have been terminated, by the defendant when the first bridge became useless, had he so elected, or had the license been so limited.” But, if it be holden that a license to erect a dam implies also a license to repair the same at pleasure, it would seem, from many authorities, that the license cannot be sustained. It is said, that such a license would give a permanent interest in the land on which the license was to be exercised, and *308that such an interest cannot be created by parol. A case in which this doctrine is laid down, in the most unequivocal terms, is that of Stevens v. Stevens, 11 Met. Rep. 251. In that case, a claim was set up by the defendant, of the right to enter upon the lands of the plaintiff at all times, to repair a dam thus erected by the defendant, under an alleged parol license, to enter to erect and repair said dam. And it was decided, that the claim could not be sustained, inasmuch as it was a claim of a permanent interest in the land of the plaintiff, and that no such interest can be created by parol.. A similar doctrine was maintained in the case of Cook v. Stearns, 11 Mass. 533. The court say: “A permanent right to hold another’s land for a particular purpose, and to enter upon it at all times without his consent, is an important interest, which ought not to pass without writing, and is the very object provided for by our statute.” In Mumford v. Whitney, 15 Wendell, 330, it was held, that a license to do an act upon another’s land, is valid; but that a parol agreement to allow a party to enter and erect a dam for a permanent purpose, was void within the statute of frauds, for the reason that it is -the transfer of an interest in the land. The right claimed in this case to erect a dam, and at pleasure repair it, is a claim of right to perpetuate the dam, as well as the exercise of the right to flow the plaintiff’s land, and in our opinion cannot be sustained in accordance with the provisions of the statute, or the law as established by the greater weight of authority.
There is still another ground upon which it is apparent that such a perpetual right to repair and maintain a dam, cannot be sustained. If the license be, in terms 'or legal effect, a license to erect and repair the dam when necessary, still, all that part of the license which relates to the repairs would be merely executory, and not executed; and so it would be revocable to that extent, according to all the authorities. No authority is found by us, which countenances the idea, that a license, not acted upon and executed without objection, is not revocable at the pleasure of the party giving the license. And it is well settled, that a license partially executed, is revocable so far as the same is not executed, and affords no protection to any one for acts *309done after revocation. Ruggles v. Lesure, 24 Pick. 187. The foregoing is a strong case in point, that a license may be partially executed, and yet that, so far as it remains unexecuted, it is revocable. The plaintiff had entered into an agreement with the defendant, that he would throw a portion of his land into the highway if the defendant would move back the plaintiff’s wall and prepare the road, and the defendant did set back the wall of the plaintiff, and while engaged in preparing the road by a removal of earth, the plaintiff forbade the removal of it; and it was held that the agreement was a mere license, and nothing more ; that it gave the defendant the right to do certain acts upon the plaintiff’s land, and was a full justification for all that was done upon it under the license, but that licenses are personal and revocable by the owner, at all times before they are exercised, and that the defendant was liable as a trespasser for all acts done after the license was thus revoked.
Cook v. Stearns, 11 Mass. Rep. 533, before cited, most distinctly recognizes a similar doctrine. The court say, “ a license is technically an authority given to do some act, or a series of acts on the land of another, without passing any estate in the land. These are held revocahle when executory, unless a definitive term is fixed, but irrevocable when executed. They amount to nothing more than an excuse for an act which would otherwise be a trespass. As to so much of the license as was not executed, it was countermandable.” See also, 5 Dane’s Abr. 577; Crosby v. Wadsworth, 6 East, 602; Tillotson v. Preston, 7 Johns. 285; Johnson v. Carter, 16 Mass. 443.
At the trial, the defendants contended that the action could not be maintained against Henry C. Redington for continuing the dam at the height at which it was in June, 1840, when he purchased, unless he was notified to remove or reduce it. In this branch of the case, two questions properly arise:
1. Was said Redington entitled to any notice to remove the timbers placed upon the dam in July, 1842, before this action could be maintained ?
2. If he was entitled to notice, was it sufficient that he should have understood from the acts of the plaintiff in reference to the *310flash-boards, or in any other respect, that the plaintiff was unwilling that the dam shall be continued ?
Now as to the first question, it is not open to doubt that no action could be maintained against H. C. Redington for permitting the dam to remain in the actual state in which he found it at the date of the purchase, until notified to remove or reduce it. So far as this question is concerned, the apparent, and not the real, state of his rights is to govern. What, then, was the actual state of the dam at that date ? The dam had settled and become ruinous as early as 1838, and had not been repaired. It appears only that “ flash-boards, so called, were occasionally put upon the dam, after it became ruinous, in very low stages of the water, till 1842.” The plaintiff’s tenants and hired men at the mill complained to the plaintiff of the use of these boards, and he told them to take them off whenever they found them upon the dam; and they did so in repeated instances. Ely and G. B. Redingtop, from whom H. C. Redington derives all his rights, several times applied to the plaintiff’s tenants and to him, for leave to put on flash-boards, and permission was given sometimes to use them for a few days at a time in low water. Whether the flash-boards were upon the dam or not at the date of the conveyance to H. O. Redington, does not appear. And we think it incumbent on him to make to appear the real state of the dam at that time. This certainly is not done. Elash-boards might or might not have been upon the dam. But that is not enough when he would shelter himself under his ignorance of the wrong done the plaintiff. If he would do that, he must first show the wrong to have been done, or the nuisance to have existed, at the time of the purchase, and then the plaintiff must have shown the defendant’s knowledge of the wrong, and notice to him to remove the nuisance, before this action could be maintained.
But upon the uncontradicted evidence in this case on this point, the plaintiff was entitled to a verdict. In July, 1842, the defendants put upon the dam some sticks of timber, which raised the dam and water higher than was authorized' by the deed. And it is not pretended that any such timbers were upon the dam at the time of the purchase in 1840. Here was a positive *311wrong done by reason of an erection by the other defendants and H. C. Redington himself. Here was a wrongful act of all the defendants. And the defendant H. C. Redington, was not entitled to any notice or request to remove this structure before the commencement of the action. No such timber was there when he purchased. If any thing was there at that time excepting the ruinous dam, it was flash-boards ; and they are not, as we have seen, shown to have been there. If flash-boards ]iad been upon the dam at the date of the purchase by H. C. Redington, and of the elevation of the dam by means of the timbers, that would have given him no right to put on the permanent timbers in 1842, after the purchase. The fact that flash-boards were found there would not have entitled H. C. Redington to notice to remove the timbers.
In the second place, as to the notice, it is made a question whether if a notice was required, it was sufficient that H. C. Redington should have understood from the plaintiff’s conduct that he was unwilling that the dam should be continued as it then was. The question arises upon the character of the notice. The sufficiency of the notice from the manner of it, and not the fact of notice, is the point to be decided.
It is to be assumed, that from the conduct of the plaintiff in regard to the removal of the flash-boards, and in other respects, the defendant well understood that the plaintiff denied the right of the defendant to keep the flash-boards upon the dam and was unwilling that it should be done, and desired their removal. And we are of the opinion that was a sufficient notice. No particular form of notice is required in such case. It is not required to be by writing. It may be written or verbal, or by acts clearly giving the party notice of the claim for a removal of the nuisance. Here was an actual removal of the flash-boards by Carleton and his agents, and full knowledge on the part of H. C. Redington of the plaintiff’s objection to their ^restoration. What further notice could be necessary, or reasonably required, than an actual removal of the nuisance and full information, from the plaintiff’s acts, of his unwillingness that it should be restored ? Any thing more would be wholly unnecessary to answer the object of the law requiring the notice at all.
*312In Bunker v. Bunker, decided in Belknap county, December term, 1847, one question was as to the sufficiency of the notice to the defendant to remove the alleged nuisance. The action was case for flowing the plaintiff’s land. The defendant had drawn down the water from the plaintiff’s land. The plaintiff verbally “forbade the defendant to flow the land again!” This was held sufficient. The court held that no particular form is required by law, in which such notice is to be. given. It must undoubtedly be so distinctly and definitely made, as that the person to whom it is addressed shall' fully understand the ground of complaint, and that the party is unwilling that the nuisance should be continued, and that he desires its removal.
And we are all of the opinion that this is all that is required, and that it is immaterial whether such notice' and information be brought home to the knowledge of the party by acts or by words. For the purposes of this case, it is not necessary to determine the question, whether Henry C. Redington, by virtue of the deed to him, of June 24th, 1840, was connected with, or took any interest in, the grant of the plaintiff, of June 23d, 1835.
The judgment, of the court is, that the verdict must be set aside and
A new trial granted.