“Hark! please,” said Mona, as just then she caught the sound of voices in the distance, “the party is returning from evening service, and I must not be found here with you.”

“I am loath to let you go, my brown-eyed sweetheart,” Ray tenderly responded.

“And I to go,” Mona answered softly, “but it is best that I should; we must both be judicious for a while—­we must not be too exacting when we have had this great new happiness come to us so unexpectedly,” and she lifted her luminous eyes to him.

He clasped her to him again.

“Good-night, my darling,” he said; then with one lingering kiss upon her lips, he let her go, and she stole softly up stairs, with a joyous heart and step, while Ray drew a paper from his pocket, and was apparently deeply absorbed in its contents when the party entered the house.

A good deal of surprise was expressed when his arrival was discovered, and he was accorded a warm welcome by the host and hostess as well as by every guest.

CHAPTER XX.

MR. RIDER MAKES AN ARREST.

While the festivities were in progress at Hazeldean, some incidents of a somewhat singular character were occurring in New York.

It will be remembered that Mr. Palmer and his son met Mrs. Montague for the first time at the reception given by Mrs. Merrill; also that their attention was attracted to a lady who wore a profusion of unusually fine diamonds—­a Mrs. Vanderheck.

We know how Ray was introduced to her, and repeated her name as Vander_beck_, with an emphasis on the beck; how she started, changed color, and glanced at him curiously as he did so, and seemed strangely ill at ease while conversing with him afterward, and a little later abruptly took her leave.

The next day, the young man communicated these suspicious circumstances to the private detective whom his father had employed to look up his stolen diamonds, and from that time Mrs. Vanderheck had been under close surveillance by that shrewd official.

Mr. Rider was a very energetic man, and, by dint of adroit inquiries and observations, learned that she was a woman who devoted most of her time to social life—­was very gay, very fond of dress and excitement of every kind.  She did not, however, resemble in any way the Mrs. Vanderbeck who had conducted the robbery of the Palmer diamonds, although, he argued, she might easily enough be an accomplice.

The detective interviewed Doctor Wesselhoff, who was now as eager as any one to assist in the discovery of those who so imposed upon him, and obtained a minute description of the other woman who had arranged for Ray Palmer to become an inmate of his institution, and he thought that possibly by the aid of a clever disguise, Mrs. Vanderheck might have figured as Mrs. Walton, the pretended mother of the pretended monomaniac.

Consequently, energetic Mr. Rider had followed close upon her track, bound to discover her real character.