momentum as a power which may be turned to beneficial purposes." The case of Mason v. Hill, 5 Barn. & Adolph, 1, contains language of an exactly similar import, used by Lord Denman in delivering the opinion of the court. See, also, Gardner v. Village of Newburgh, 2 John. Ch., 162. § 96. Mr. Chancellor Kent's opinion noticed. Mr. Chancellor Kent has also summed up the same doctrine with his usual accuracy in the brief, but pregnant, text of his commentaries (3 Kent's Comm., Lect. 43, p. 439, 3d edit.); and I scarcely knew where else it can be found reduced to so elegant and satisfactory a formulary. In the old books the doctrine is quaintly though clearly stated; for it is said that a water-course begins ex jure naturæ, and having taken a certain course naturally, it cannot be [lawfully] diverted. Aqua currit, et debet currere, ut currere solebat. Shurry v. Pigott, 3 Bulst., 339; S. C., Popham, 166. 97. The natural flow of a stream cannot be interrupted by one proprietor to the detriment or prejudice of another proprietor. The same principle applies to the owners of mills on a stream. They have an undoubted right to the flow of the water as it has been accustomed of right and naturally to flow to their respective mills. The proprietor above has no right to divert or unreasonably to retard this natural flow to the mills below; and no proprietor below has a right to retard or turn it back upon the mills above to the prejudice of the right of the proprietors thereof. This is clearly established by the authorities already cited; the only distinction between them being, that the right of a riparian proprietor arises by mere operation of law, as an incident to his ownership of the bank, and that of a mill owner as an incident to his mill. Bealey v. Shaw, 6 East, 208; Saunders v. Newman, 1 B. & Ald., 258; Mason v. Hill, 3. B. & Adolph., 304; S. C., 5 B. & Adolph., 1; Blanchard v. Baker, 8 Greenl., 253, 268; and Tyler v. Wilkinson, 4 Mason, 397, 400 to 405, are fully in point. Mr. Chancellor Kent, in his commentaries, relies on the same principles, and fully supports them by a large survey of the authorities. 3 Kent, Comm., Lect. 52, p. 441 to 445, 3d edit. § 98. Where the diverting of the water amounts to a mere temporary trespass. Now, if this be the law on this subject, upon what ground can the defendants insist upon a diversion of the natural stream from the plaintiff's mills, as it has been of right accustomed to flow thereto? First, it is said that there is no perceptible damage done to the plaintiffs. That suggestion has been already in part answered. If it were true it could not authorize a diversion, because it impairs the right of the plaintiffs to the full, natural flow of the stream, and may become the foundation of an adverse right in the defendants. In such a case actual damage is not necessary to be established in proof. The law presumes it. The act imports damage to the right, if damage be necessary. Such a case is wholly distinguishable from a mere fugitive, temporary trespass, by diverting or withdrawing the water a short period without damage, and without any pretense of right. In such a case the wrong, if there be no sensible damage, and it be transient in its nature and character, as it does not touch the right, may possibly (for I give no opinion upon such a case) be without redress at law; and certainly it would found no ground for the interposition of a court of equity by way of injunction. But I confess myself wholly unable to comprehend how it can be assumed in a case like the present that there is not and cannot be an actual damage to the right of the plaintiffs. What is that right? It is the right of having the water flow in its natural current at all times of the year to the plaintiff's mills. Now, the value of the mill privileges must essentially depend, not merely upon the velocity of the stream, but upon the head of water which is permanently maintained. The necessary result of lowering the head of water permanently would seem, therefore, to be a direct diminution of the value of the privileges. And, if so, to that extent it must be an actual damage. Again, it is said that the defendants are mill owners on the lower dam, and are entitled as such to their proportion of the water of the stream in the natural flow. Certainly they are. § 99. The defendants entitled to their proportion of the flow of water at the lower dam, for there is the place their right attaches. But where are they so entitled to take and use it? At the lower dam; for there is the place where their right attaches, and not at any place higher up the stream. Suppose they are entitled to use for their own mills on the lower dam half the water which descends to it; what ground is there to say that they have a right to draw off that half at the head of the mill-pond? Suppose the head of water at the lower dam in ordinary times is two feet high; is it not obvious that, by withdrawing at the head of the pond one-half of the water, the water at the dam must be proportionally lowered? It makes no difference that the defendants insist upon drawing off only one-fourth of what they insist they are entitled to; for, pro tanto, it will operate in the same manner; and if they have a right to draw off to the extent of one-fourth of their privilege, they have an equal right to draw off to the full extent of it. The privilege attached to the mills of the plaintiff is not the privilege of using half, or any other proportion merely, of the water in the stream, but of hav ing the whole stream, undiminished in its natural flow, come to the lower dam with its full power, and there to use his full share of the water-power. § 100. Where two parties own a water right at a certain dam in the stream, the law presumes that they hold a right to the entire stream undiminished in its natural flow on its arrival at the dam. The plaintiff has a title, not to a half or other proportion of the water in the pond, but is, if one may so say, entitled per my et per tout to his proportion of the whole bulk of the stream, undivided and indivisible except at the lower dam. This doctrine, in my judgment, irresistibly follows from the general principles already stated; and what alone would be decisive, it has the express sanction of the supreme court of Maine in the case of Blanchard v. Baker, 8 Greenl., 253, 270. The court there said in reply to the suggestion that the owners of the eastern shore had a right to half the water and a right to divert it to that extent: "It has been seen that, if they had been owners of both sides, they had no right to divert the water without again returning it to its original channel [before it passes the lands of another proprietor]. Besides, it was inpossible in the nature of things that they could take it from their side only. An equal portion from the plaintiff's side must have been mingled with all that was diverted." § 101. It is no answer to plaintiff's complaint that the defendant had increased the quantity of water in the stream by an act wholly his own. A suggestion has also been made that the defendants have fully indemnified the plaintiff from any injury, and in truth have conferred a benefit on him by securing the water by means of a raised dam higher up the stream, at Sebago Pond, in a reservoir, so as to be capable of affording a full supply in the stream in the dryest seasons. To this suggestion several answers may be given. In the first place, the plaintiff is no party to the contract for raising the new dam and has no interest therein, and cannot, as a matter of right, insist upon its being kept up, or upon any advantage to be derived therefrom. In the next place, the plaintiff is not compellable to exchange one right for another, or to part with a present interest in favor of the defendants at the mere election of the latter. Even a supposed benefit cannot be forced upon him against his will; and, certainly, there is no pretense to say that, in point of law, the defendants have any right to substitute, for a present existing right of the plaintiff's, any other which they may deem to be an equivalent. The private property of one man cannot be taken by another simply because he can substitute an equivalent benefit. Having made these remarks upon the points raised in the argument, the subject, at least so far as it is at present open for the consideration of the court, appears to me to be exhausted. Whether, consistently with this opinion, it is practicable for the defendants successfully to establish any substantial defense to the bill, it is for the defendants, and not for the court, to consider. I am authorized to say that the district judge concurs in this opinion. Decree accordingly. TYLER v. WILKINSON. (Circuit Court for Rhode Island: 4 Mason, 397-413. 1827.) Opinion by STORY, J. STATEMENT OF FACTS.-This is a very important case, complicated in facts and voluminous in testimony. It will not, however, be necessary to go over the details of the proofs, or even of the arguments, urged at the bar, further than may serve to explain the opinion of the court, and give a clear understanding of the points in controversy. The river Pawtucket forms a boundary line between the states of Massachusetts and Rhode Island, in that part of its course where it separates the town of North Providence from the town of Seekonk. It is a fresh-water river above the lower falls between these towns, and is there unaffected by the ebb or flow of the tide. At these falls there is an ancient dam, called the lower dam, extending quite across the river, and several mills are built near it, as well on the eastern as on the western side of the river. The plaintiffs, together with some of the defendants, are the proprietors in fee of the mills and adjacent land on the eastern bank, and either by themselves or their lessees are occupants of the same. The mills and land adjacent, on the western bank, are owned by some of the defendants. The lower dam was built as early as the year 1718 by the proprietors on both sides of the river, and is indispensable for the use of their mills respectively. There was previously an old dam on the western side, extending about three-quarters of the way across the river, and a separate dam for a saw-mill on the east side. The lower dam was a substitute for both. About the year 1714 a canal was dug, or an old channel widened and cleared, on the western side of the river, beginning at the river a few rods above the lower dam, and running round the west end thereof, until it emptied into the river about ten rods below the same. dam. It has been long known by the name of Sergeant's Trench, and was originally cut for the passage of fish up and down the river; but having wholly failed for this purpose, about the year 1730 an anchor-mill and dam were built across it by the then proprietors of the land, and between that period and the year 1790 several other dams and mills were built over the same, and since that period more expensive mills have been built there, which are all owned by some of the defendants. About thirty years before the filing of the bill, to wit, in 1792, another dam was built across the river at a place above the head of the Trench and about twenty rods above the lower dam, and the mills on the upper dam, as well as those on Sergeant's Trench, are now supplied with water by proper flumes, etc., from the pond formed by the upper dam. The proprietors of this last dam are also made defendants. Without going into the particulars of the bill (for in consequence of intervening deaths and devises the cause is now before the court upon a supplemental bill, in the nature of a bill of revivor), it is necessary to state that the bill charges that the owners of Sergeant's Trench are entitled, as against the owners of the lower dam, only to what is called a waste-water privilege, that is, to a right to use only such surplus water as is not wanted by the owners of the lower dam and lands for any purposes whatever. In other words, that the right of the owners of Sergeant's Trench is a subservient right to that of the plaintiffs, and takes place only as to any water which the plaintiffs may not, from time to time, have any occasion to use for any mills erected, or to be erected, by them. It charges a fraudulent combination between the owners of the upper dam and Sergeant's Trench injuriously to appropriate and use the water, and that the latter appropriate a great deal more water than they are entitled to by ancient usage, and waste the water to the injury of the plaintiffs. The object of the bill is to establish the right of the plaintiffs and to obtain an injunction and for general relief. The principal points which have been discussed at the bar are, first, what is the nature and extent of the right of the owners of Sergeant's Trench; and, secondly, whether that right has been exceeded by them to the injury of the plaintiffs. Before proceeding to an examination of these points it may be proper to ascertain the nature and extent of the right which riparian proprietors generally possess to the waters of rivers flowing through their lands. Unless I am mistaken, this will relieve us from a great portion of the difficulties which incumber this cause and lead us to a satisfactory conclusion upon its merits. I shall not attempt to examine the cases at large or to reconcile the various dicta which may be found in some of them. The task would be very onerous, and I am not aware that it would be very instructive. I have, however, read over all the cases on this subject which were cited at the bar or which are to be found in Mr. Angell's valuable work on water-courses, or which my own auxiliary researches have enabled me to reach. The general principles which they contain and support, I do not say in every particular instance, but with a very strong and controlling current of authority, appear to me to be the following: § 102. Riparian rights stated. Prima facie every proprietor upon each bank of a river is entitled to the land, covered with water, in front of his bank, to the middle thread of the stream, or, as it is commonly expressed, usque filum aquæ. In virtue of this ownership he has a right to the use of the water flowing over it in its natural current, without diminution or obstruction. But, strictly speaking, he has no property in the water itself, but a simple use of it while it passes along. The consequence of this principle is that no proprietor has a right to use the water to the prejudice of another. It is wholly immaterial whether the party be a proprietor above or below in the course of the river; the right being com mon to all the proprietors on the river, no one has a right to diminish the quantity which will, according to the natural current, flow to a proprietor below, or to throw it back upon a proprietor above. This is the necessary result of the perfect equality of right among all the proprietors of that which is common to all. The natural stream, existing by the bounty of Providence for the benefit of the land through which it flows, is an incident annexed by operation of law to the land itself. When I speak of this common right, I do not mean to be understood as holding the doctrine that there can be no diminution whatsoever, and no obstruction or impediment whatsoever, by a riparian proprietor in the use of the water as it flows, for that would be to deny any valuable use of it. There may be and there must be allowed of that which is common to all, a reasonable use. The true test of the principle and extent of the use is whether it is to the injury of the other proprietors or not. There may be a diminution in quantity, or a retardation or acceleration of the natural current indispensable for the general and valuable use of the water, perfectly consistent with the existence of the common right. The diminution, retardation or acceleration, not positively and sensibly injurious by diminishing the value of the common right, is an implied element in the right of using the stream at all. The law here, as in many other cases, acts with a reasonable reference to public convenience and general good, and is not betrayed into a narrow strictness subversive of common sense, nor into an extravagant looseness which would destroy private rights. The maxim is applied, sic utere tuo, ut non alienum lædas. But of a thing common by nature, there may be an appropriation by general consent or grant. Mere priority of appropriation of running water, without such consent or grant, confers no exclusive right. It is not like the case of mere occupancy where the first occupant takes by force of his priority of occupancy. That supposes no ownership already existing, and no right to the use already acquired. But our law annexes to the riparian proprietors the right to the use in common as an incident to the land; and whoever seeks to found an exclusive one must establish a rightful appropriation in some manner known and admitted by the law. Now this may be either by a grant from all the proprietors whose interest is affected by the particular appropriation, or by a long exclusive enjoyment without interruption, which affords a just presumption of right. By our law, upon principles of public convenience, the term of twenty years of exclusive uninterrupted enjoyment has been held a conclusive presumption of a grant or right. I say of a grant or right, for I very much doubt whether the principle now acted upon, however in its origin it may have been confined to presumptions of a grant, is now necessarily limited to considerations of this nature. The presumption is applied as a presumption juris et de jure, wherever by possibility a right may be acquired in any manner known to the law. Its operation has never yet been denied in cases where personal disabilities of particular proprietors might have intervened, such as infancy, coverture and insanity, and where, by the ordinary course of proceeding, grants would not be presumed. In these and in like cases there may be an extinguishment of right by positive limitations of time, by estoppels, by statutable compensations and authorities, by elections of other beneficial bequests, by conflicting equities and by other means. The presumption would be just as operative as to these modes of extinguishment of a common right as to the mode of extinguishment by grant. These are the general principles which appear to me applicable to the pres |