The defendants, therefore, insist that as the plaintiffs or their predecessors had no title to any portion of the street, the consent of their predecessors, while in the possession and ownership of the abutting land, that the defendants might construct and operate the railroad in the square in front of their land, was more than a mere license to do an act on the land of the licensor, and that it amounted in law and in fact to an abandonment of their rights or easements in the street so far as was necessary for the construction and operation of the railroad, and that the consent to such construction having been acted on and large amounts of money expended on the faith thereof, the plaintiffs as the successors of those who gave the consent are themselves estopped from making any claim for damages arising from such construction and operation. It has been the law in this State for a number of years, that an easement to do some act of a permanent nature on the land of another can be created only by a deed or conveyance in writing, operating as a grant, and that a consent in writing on the part of the landowner is no more valid than if it were by parol.

1 There are two distinct cases involved under this heading: (I) After the licensee has done the act or series of acts for which the permission was given, may the licensor revoke the license so as to hold the licensee for trespass on account of such acts? (2) Has the licensor a right to forbid the continued maintenance of a condition which resulted from the doing of the act or series of acts? The customary treatment of the subject has been followed here, but the student should observe that some of the cases come under one query some under the other. - Ed.

2 See cases generally under this chapter. - Ed.

Thus a parol agreement by the owner of the land that a person may abut and erect a dam on such land, not for a temporary purpose, but for a permanent use such as the creation of a water power for the use of mills, is void, and the agreement being a mere license may be revoked even after it has been acted upon by the other party. Also a permanent easement to drain through the land of another is not created by a license so to do, even when in writing and made upon a good consideration. Mumford v. Whitney, 15 Wend. 381; Wiseman v. Lucksinger, 84 N. Y. 31 ; Cronkhite v. Cronk-hite, 94 Id. 323; Babcock v. Utter, 1 Abb. Ct. of App. Dec. 27, and cases cited; Eckerson v. Crippen, no N. Y. 585.

The question of the establishment of an easement by adverse user, which may authorize the presumption of a grant, is not involved, nor is the ability to thus prove its existence denied. Hammond v. Zehner, 21 N. Y. 118. It is, however, held, what would otherwise seem to be plain enough, that there can be no adverse user where the right to use exists and is exercised under a license. 84 N. Y. 31, supra.

The reasoning upon which these decisions as to the insufficiency of a license are based, is that the right which is claimed under a license amounts to an interest in land and that such interest cannot be created and cannot pass to another without a proper conveyance or grant of such interest in writing and under seal as required by our statute. It is said that a license is a mere authority to enter upon the land, and is a sufficient protection to the licensee while it lasts, but that it may be revoked at any time, and after its revocation it cannot be used as a protection for any future acts. It is held there can be no equitable estoppel which will operate to prevent the revocation of the license, grounded upon the fact that the licensee has entered upon the land of the licensor and expended thereon labor and money upon the faith of the license, because it must be held that the licensee knew that the license gave him no interest in the land, and that he must rely only upon the indulgence of the licensor, and if that be withdrawn he must himself withdraw from the land. Otherwise, it is said, the statute in regard to the creation and conveyance of interest in land would be in great part abrogated. The easements of abutting owners in New York city, who are without title to any portion of the streets upon which their lands abut, differ somewhat in their origin from ordinary easements. They have not been created by grant or covenant, but it is said of them that it is easier to realize their existence than to trace their origin; that they arise from the situation, the course of legislation, the trust created by statute, the acting upon the faith of public pledges and upon a contract between the public and the property owner, implied from all the circumstances, that the street shall be kept open as a public street, and shall not be devoted to other and inconsistent uses. Kane Case, 125 N. Y., supra. Whatever the means by which the easements were created they are in their nature the same as if they had been created by grant. The owners thereof cannot be divested of them without their consent unless they are compensated therefor. Although it may generally be said, under the authority of the cases already cited, that an easement in the nature of an interest in the land of another can only be created by a grant, yet after it has been created and while it is in existence, it may be abandoned and thus extinguished by acts showing an intention to abandon and extinguish the same. This has been many times decided and by many different courts. A cesser to use, accompanied by an act clearly indicating an intention to abandon the right, would have the same effect as a release without reference to time. Snell v. Levitt, 110 N. Y. 595, and cases cited in opinion of Earl, J., at page 603. The intention to abandon is the material question and it may be proved by an infinite variety of acts. If a third party interested in the servient estate has acted upon such abandonment, and in regard to whom it would operate unjustly if the exercise of the easement should be resumed in favor of the dominant estate, added force is given to the claim of abandonment. Id.