A conveyance of real property, within the state, heretofore executed, and heretofore acknowledged or proved, and certified, so as to be entitled to be read in evidence, or recorded, under the laws in force at the time when so acknowledged or proved, but which has not been recorded is entitled to be read in evidence, and recorded in the same manner, and with the like effect, as if this chapter had not been passed. If heretofore executed, but not proved or acknowledged, it may be proved or acknowledged in the same manner as conveyances hereafter executed and with like effect.