The above oil painting of St Margaret is by Raphael, 1518, and is located at Kunsthistoriches, Vienna. It is a monumental piece.
I took a photo of the salon style room where it is currently exhibited. As you can see (left), the room is "littered" with old master paintings and it is impossible to take them all in. The paintings highest on the wall are the most neglected.
In this Raphael version, the dragon's open mouth (above closeup) is approximately the size of a human head with room to spare- in other words there's just enough room for you. It couldn't be more creepy. The reptilian body is so life-like that it caused both Paul, my son, and I to simultaneously take a step back in awe and repulsion. So when her feast day popped up in my emails, I instantly recalled this version.
Also, note how calm the maiden Margaret remains despite what appears to be her impending doom- she's trapped in a deep gully with that wretched, writhing, howling thing. However, the light of grace illuminates her figure, a halo of sanctity encircles her head and a red cloth (red symbolizing the blood of Christ) drapes her inner arm which holds on firmly to the crucifix. Wow. All is well.
"Although St Margaret was declared to be apocryphal in the year 494 by no less an authority than Pope Gelasius, and many people over many years have entertained doubts about her authenticity, she is still widely venerated as a saint today." - See more
Virgin and martyr; also called MARINA; belonged to Pisidian Antioch in Asia Minor, where her father was a pagan priest. Her mother dying soon after her birth, Margaret was nursed by a pious woman five or six leagues from Antioch. Having embraced Christianity and consecrated her virginity to God, she was disowned by her father and adopted by her nurse. While she was one day engaged in watching the flocks of her mistress, a lustful Roman prefect named Olybrius caught sight of her, and attracted by her great beauty sought to make her his concubine or wife. When neither cajolery nor threats of punishment could succeed in moving her to yield to his desires, he had her brought before him in public trial at Antioch. Threatened with death unless she renounced the Christian faith, the holy virgin refused to adore the gods of the empire and an attempt was made to burn her, but the flames, we are told in her Acts, left her unhurt. She was then bound hand and foot and thrown into a cauldron of boiling water, but at her prayer her bonds were broken and she stood up uninjured. Finally the prefect ordered her to be beheaded.
The Greek Church honors her under the name Marine on 13 July; the Latin, as Margaret on 20 July. Her Acts place her death in the persecution of Diocletian (A.D. 303-5), but in fact even the century to which she belonged is uncertain. St. Margaret is represented in art sometimes as a shepherdess, or as leading a chained dragon, again carrying a little cross or a girdle in her hand, or standing by a large vessel which recalls the cauldron into which she was plunged. Relics said to belong to the saint are venerated in very many parts of Europe; at Rome, Montefiascone, Brusels, Bruges, Paris, Froidmont, Troyes, and various other places. Curiously enough this virgin has been widely venerated for many centuries as a special patron of women who are pregnant.
image right: St. Marina (Margaret) the Great-Martyr. An illustration in her hagiography printed in Greece depicting her beating a demon with a hammer. wikipedia.