The Time Mirror

Here was a strange mirror indeed! It reflected an image all right, but not an image from the same era in history!
Pale moonlight spilled through the window and over the wedding gifts that crowded the little room.
And this mirror, darling? Mark Carter asked. Who sent it?
A sudden flicker of worry flashed across Elaine Duchard's lovely face. She bit her lower lip nervously. Pretended to inspect a great silver punchbowl that stood on a nearby table.
Who did you say sent the mirror? her sweetheart repeated.
Still another moment of taut hesitation. At last:
It's from Adrian Vance, Mark.
Adrian Vance!
Mark spat the name as if it were an epithet.
Sshhh! Not so loud! A pause. He's an old friend, dear. I can't forbid him to send us a present. After all he's just trying to be polite.
The man's brown eyes were smouldering. Those were fine company manners he showed off the night you told him you were going to marry me instead of him!
Then, savagely: