How have the words "Prior Registration" ever been interpreted?

In a carefully considered judgment of Mowat, V.C., 17 Gr. 379, Forrester v. Campbell, it was held that these words could not have had the effect contended for, chiefly, as I read it, because many or most equitable liens or interests in land are created by deed, and the preceding clauses clearly postpone the prior registration as against an unregistered prior deed of which there was actual notice.