In a property matter, judgment entitling defendants to make any use of an easement area that does not interfere with plaintiffs' use of the same is reversed in part, and affirmed in part as modified where: 1) the exclusive use of a defined area of the servient tenement by the owners of the dominant tenement was not prohibited under state law; 2) the language of the instrument by which the easement was created clearly expressed an intention that the use of the easement be exclusive to the owners; and 3) a question remained as to whether there was any conceivable use of the subsurface of, or the air rights above, the easement area that would be consistent with the intended exclusive use of the surface of the easement area.