An executor or administrator shall be deemed to have notice only to mortgages (but not of the bonds accompanying such mortgages) and of such judgments as would be liens against real estate at the date of death of the decedent, which mortgages and judgments are of record in the county of this State in which letters were granted upon the estate of the decedent, unless there has been a failure to insert them in the general indices of the office wherein it is proper that they be recorded.