When the subject matter of a conveyance is sought to be identified by reference to boundaries indicated by monuments of appreciable width, inevitably the question arises as to the particular part of the monument which is to control. It is agreed that prima facie the center point or line is to be taken. There is in this rule the practical value of ascertainable certainty; besides, it has, an inherent reasonableness that commends it. The rule, however, should not be applied when a result would be produced that would not accord with what other considerations show pretty clearly must have been intended. For example, if the grantor owned only to the near side of the monument, the center should not be the boundary; and if the grantor owned to the far side but not beyond, it may well be that the entire monument should be deemed to lie within the tract conveyed. A reference to "the land of X" as a boundary certainly would not call for the middle line of the monument.