There once lived in Florence, in the Via dei Velluti, a lady young and beautiful, yet who was for all that a witch, who knew many strange and curious things, which she kept to herself, for truly the cleverest witches and wizards are those who are the least suspected.

However, she had fixed her love on a certain young gentleman of great family, who had a friend who was, like himself, much liked by everybody. Now it befell by a strange chance that these two met suddenly one dark night in the Piazza Santa Maria Novella as they turned the corner; each, believing that the other was some enemy or assassin, drew his sword, and as they were fighting, the guards, or police, arrested them and took them to prison or to the Bargello.

Now, owing to many disorders caused by quarrels and frequent deaths, the Council and the Duke had strictly prohibited all duelling, and condemned to axe or halter all who should be found with weapons drawn. Therefore these young gentlemen were in great peril, since no one believed their story.

In this strait the beautiful witch, or Signorina la Maga, sent to the Duke an intelligent messenger, who said:
– "Signore Duca, these two young gentlemen swear by the sword of St. Peter, who also drew blade when he was in a passion, that they met in the dark, neither recognising the other, each mistaking the other for an assailant, which may very well have been the truth; and if so, it would be most cruel to put to death two innocent men. And the more so because there is a doubt in the case, of which the accused should always have the benefit.
– Now there is here in Florence a lady who has the art of showing in a blessed mirror all things which have been, just as they were, and it seems to me that if her truth can be well tested in something else, it would be but just to learn from her how this duel or encounter really came to take place.
– “‘Davvero!' replied the Duke, 'that seems to me to be but sensible, for I have heard wondrous tales of these magic mirrors, and I can easily test the lady's power. Therefore bid her come.

So, on the evening appointed, the Duke assembled many ladies and gentlemen in a darkened room, awaiting the wonder. Then the signora burned incense, and common and coarse salt, and pronounced the following incantation :
" Fairy of the Hundred Stars,
I conjure thee,
For in this moment I have need
If thine aid.
By myself I can do naught.
I fain would save from the vengeance of the Duke
The one whom he would hang.

Fairy of the Hundred Stars,
I call on thee for aid;
On thee and the Beautiful Marta,
That I may save these two young men.
May the salt in this instant
Change to the Fairy of the Hundred Stars,
The incense become the Beautiful Marta,
And the cummin a hundred devils,
Who may open the door of the Bargello
To my lover, and unto his friend, and unto all
Who are imprisoned.

While she said this, the salt and incense, or the smoke which rose from them, became two beautiful spirits, which were the Fairy of the Hundred Stars and the Beautiful Marta. Then all beheld in a great circle the Church of Santa Maria Novella, with the Piazza, and then the two young men, who, encountering blindly in the dark, drew their swords, and fought till the guards seized them, when all vanished in darkness, with the two spirits.

And when the room was again lighted all present were awed, yet charmed, at what they had seen, and the Duke said :
– Truly if the fairies and imps have not already set the young men free, it shall be done forthwith. Yet ere it be effected, fair lady, I would fain test the truth of thine art more closely. Canst thou show me what I myself was doing at that very hour of that night?'
– Yes, your highness; but it may be that this is a thing that others should not know.
– Nonsense,' replied the Duke; 'I care not if all the Court knows it; and I am sure that half of them do, who will assuredly tell the other half.

"hen the witch darkened the room, and the Duke saw himself, as did all present, embracing a very beautiful lady. At which there was a roar of laughter, in which the Duke joined.

– But it seems to me,' said the Duke aside, sotto voce, to the witch, 'that while this lady bears an extraordinary likeness to my friend of that evening, still it is not exactly the same person.
– 'Speak lower, your highness,' exclaimed the witch, 'and I will tell you a secret-and the truth.
– 'That lady whom you thought you had met, had on that evening another affair on hand, or other fish to fry. So she sent her twin sister in her place, thinking that you would never find it out!'
– ‘Dia-volo!' cried the Duke. 'It appears that I, thinking to eat veal, devoured chicken without knowing it.
I always liked the other sister best, but never dared make love to her, thinking she was such a virtue. And now I have made love to her in very deed and never knew it.

'Ah, well! a fair exchange is no robbery. True it is what I have often heard :
"The ways of Fate are wonderful and deep,
Fortune to many comes while they're asleep.”