Oker owned in fee simple two adjoining lots, Lots 1 and 2. He conveyed in fee simple Lot 1 to Frank. The deed was in usual form of a warranty deed with the following provision inserted in the appropriate place: "Grantor, for himself, his heirs and assigns, does covenant and agree that any reasonable expense incurred by grantee, his heirs and assigns, as the result of having to repair the retaining wall presently situated on Lot 1 at the common boundary with Lot 2, shall be reimbursed one-half the costs of repairs; and by this provision the parties intend a covenant running with the land." Frank conveyed Lot 1 in fee simple to Sara by warranty deed in usual and regular form. The deed omitted any reference to the retaining wall or any covenant. Fifty years after Oker's conveyance to Frank, Sara conveyed Lot 1 in fee simple to Tim by warranty deed in usual form; this deed omitted any reference to the retaining wall or the covenant. There is no statute that applies to any aspect of the problems presented except a recording act and a statute providing for acquisition of title after ten years of adverse possession. All conveyances by deeds were for a consideration equal to fair market value. The deed from Oker to Frank was never recorded. All other deeds were promptly and properly recorded. Lot 2 is now owned by Henry, who took by intestate succession from Oker, now dead. Tim expended $3,500 on the retaining wall. Then he obtained all of the original deeds in the chain from Oker to him. Shortly thereafter, Tim discovered the covenant in Oker's deed to Frank. He demanded that Henry pay $1,750, and when Henry refused, Tim instituted an appropriate action to recover that sum from Henry. In such action, Henry asserted all defenses available to him. defenses available to him. If judgment is for Henry, it will be because 
Tim is barred by adverse possession. Frank's deed from Oker was never recorded. Tim did not know about the covenant until after he had incurred the expenses and, hence, could not have relied on it.  Tim's expenditures were not proved to be reasonable and customary.