She soon brushed them away, however, and lifting the mirror, examined it carefully.

She found that the tiny drawer would shove smoothly in and out, and she pushed it almost in, but took care not to quite close it.

“There must be a spring somewhere to hold it in place,” she murmured, regarding it curiously.  “Ah! now I feel it!  But how is it operated?  How can the drawer be opened again if I shut it entirely?”

She looked the mirror over most carefully, both on the back and front, but at first could detect nothing.  But at length, as she still continued to work the drawer in and out, she noticed that the central pearl and gold point at the top of the frame moved slightly as she pressed the drawer close upon the spring, and she believed that she had discovered the Secret of the Royal Mirror.

With a resolute air she shut it entirely and heard the click of the spring as it shot into its socket.  Her reason told her that pressure applied to that central point of pearl and gold would at once release the drawer again.

She tried it, and instantly it dropped out upon her lap.

“It is the strangest thing in the world.  I feel almost as if I had opened a grave,” she murmured, a shiver running along her nerves.  “My heart almost fails me when I think of examining its contents—­this letter addressed to me, this package of letters, and the tiny box.  I wonder what there is in it?”

She looked strangely beautiful as she sat there upon the floor, her face startlingly pale, her eyes seeming larger than ever, with that wondering expression in their liquid depths, while she turned that little box over and over in her trembling hands, as if she tried to gather courage to untie the string that bound its cover on and look within it.

At last she threw up her head with a determined air, gathered up all the things she had found in the secret drawer, and rising, drew a chair to her table, where she sat down to solve the mystery.

CHAPTER XIII.

“I SHOULD THINK WE WERE OUT AT SEA!”

Mona’s curiosity prompted her to examine the contents of the little box first.

She untied the narrow ribbon that was bound about it, lifted the cover and a layer of cotton, and discovered the two rings which we already know about.

“My mother’s wedding and engagement-ring!” Mona breathed, seeming to know by instinct what they were.  “They must have been taken from her fingers after she was dead, and Uncle Walter has kept them all these years for me.  Oh, why could he not have told me about them?  I should have prized them so.”  She lifted them from their snowy bed with reverent touch, remarking, as she did so, the size and great beauty of the diamond in the engagement-ring.

“My dear, deeply wronged mother! how I should have loved you!” she murmured.  “I wonder if you know how tenderly I feel toward you; if you can see me now and realize that I, the little, helpless baby, for whose life you gave up your own, am longing for you with all my heart and soul.”