Numerous stories, some apocryphal, some true, abound in the literature describing the spread of devotion to Mary through the use of the Hail Mary. One legend recorded widely during this period tells the amusing story of Eulalia, who was very devoted to the Blessed Virgin. One day our Lady appeared to the holy woman. Although Eulalia was at first alarmed, the legend tells us that the apparition reassured her in the following words:
"Do not, my daughter, be afraid of the fond Mother to whom each weekday you pay all homage in your power. But I caution you that if you wish the services you render me to benefit yourself more and to be more acceptable to me, then do not in the future pronounce the words [of the Hail Mary] so rapidly, for let me tell you that when you greet me with the Angelical Salutation, I experience a great thrill of joy, and more especially when you utter lingeringly the words Dominus tecum [the Lord is with you]. The delight I feel then is more than can be expressed in words. For then it seems to me that I feel my Son within me even as He, true God and man, was with me when he vouchsafed to be born of me for the sake of sinners. And this was an unspeakable joy for me at that time, so is it now when Dominus tecum is said to me in the Angelical Salutation."
Taken from The History and Devotion of the Rosary by Richard Gribble, C.S.C.