The narrow range of the class of rights under consideration, the restrictions which the pats imposes upon their creation and exercise. have been made clear by the foregoing explanation of their legal charaeter and status. This jealous attitude of the law toward rights of this char acter is 411w to the fact that they always consti tute an interferenee with the free exercise of his natural rights by the owner of the servient tenement. The easy creation and the indefinite multiplication of such rights would produee grave inconvenience and would seriously hamper the free alienation of real property. Hence the common law has still further restricted them by arbitrarily limiting their number. it is a maxim of the law that no novel easements can lie created. Land owners are limited to the kinds which have always been known, and which have previously been recognized by the courts as proper and convenient burdens upon land. Those already referred to—ways. lights, drains, watercourse. support to buildings comprehend practically all or nearly all, such rights as can be created. Attempts have been made to increase the number. but the courts have invariably re fused to countenance such proposed additions to the hst, Its the right of avec.: of wind to a wind mill or a chimney, the right to an unobstructed view, etc. Such a right may indeed. be con ferred upon one man Iu another, hut it remains a mere right in in rsonum, a contract right, and does not become a burden upon the land of the grantor or an appurtenance to the estate of the grantee. The only exception to this principle is that furnished by the ease of the 'equitable easement.' whereby a restrictive covenant affect• ing the use of land—as an agreement not to build within a certain distance of the street line— is enforeeable in equity—not only against the maker of the covenant and his heirs, hut also against his assigns who take title with notice of the understanding. I'mt even this exception. important though it he, is limited to a narrow range of eases. in which the eovenant sought to be enforced is purely restrictive in character and imposes no active duty upon the owner of the premises affected.
Analogous to easements in their effects, hut differing fundamentally from them in character, are the rights which are loosely deseribell as 'covenants running with the land.' It has already been stated that an easement cannot be created by covimant—which is only a contract under seal--but requires the ancient form of a grant. Interests, or estates, in real property, whether corporeal or incorporeal. are too im portant to be subject to creation or transfer by any but the most solemn legal forms. Hence a covenant affecting the use of land. like any other covenant, creates only a right in pet-swoon, a right of action on contract, and not an interest iu the property itself. But if such right of
action runs with the land, that is. if it hinds any and everybody who becomes the owner of the land. and if. on the other hand, it is enforce able, not only by the person In whop' the promise is made, hut by everybody who become: entitled to the promisee's land, it is evident lhat we have the substance if not the form of an ease ment. The method of enforcing the right is dif ferent, by an action in covenant instead of tres pass. but the right, on the one hand. and the burden, on the other. are Writ otherwise distin guishable from those resulting from an mein. In a very limited class of en-c-, such rights. arising out of covenant. are recognized in our law. The essential conditions are: ( I that the envenant shall 'touch and eoncern' the land, that is. that it shall affect the use and eon dition of the premises: and (21 that there shall be privity of estate, that is, some such relation as that of landlord and tenant, between the parties. In other words, hoth parties oust in a le7a1 sense be owners of the properly affected. Thus, if a tenant covenants to make a certain Blass of repairs. or to cultivate the land in a certain way, the right to enforce such covenant will pass to the landlord's assignee. and the obli gation to perform it will be equally incumbent on the tenant's assignee as upon the original tenant who entered into the engagement. in a few American jurisdictions this principle has been extended to the case of the priviti exist ing between the owners of a dominant and a ser vient tenement, respectively. so that a covenant by the latter to keep a private way over his land in repair tor the benefit of the former would pass as a permanent burden with the land. but this extension of the common-law doctrine is not generally accepted in the United State. nor in England.
There is. of course, no element of casement in the other class of cases to which the expres sion 'covenant running with the land' is ap plied—those, namely, where, then. being no rela tion of privity of estate, a uovenant for the benefit of a parcel of land. by whomsoever made, is enforceable by those to whom the land may pass by descent or otherwi:e, against the cove nanting party. Here we have the exact reverse of what is erroneously termed an easement in gross—the latter being a right in land claimed by au individual in his personal capacity, and tile former a right vested in the land. or in its tenant for the time being. against an individual. There being no servitude. there is no easement, which. as has been said before. requires both a dominant and a servient tenement. See INcon