"I am very sorry," Mona returned, flushing, "but after you went out to drive I a.s.sisted the chambermaid, who was nearly crazy with the toothache, to put some of the rooms in order; then, as you had not returned, I went out for a little walk."

"Well, I don't mind about the walk, but I didn't bring you with me to do chamber-work in every hotel we stop at," sharply retorted the much annoyed lady. "You can go at the gloves right away," she added; "then I shall want you to help me pack, for we are to leave on the first boat to-morrow morning. And," she concluded, thus explaining to Mona her unusual irritability, "we've got to make the trip alone, after all, for my friend is worse this morning, and so the whole family have given it up."

"I am sorry that you are to be disappointed. I should suppose you would wish to give it up yourself. I am afraid you will not enjoy it at all,"

Mona replied, wondering why she did not at once return to New York instead of keeping on.

"Of course, I shall not enjoy it," snapped the woman, but bestowing a searching glance upon her companion, "and I would not go on, only Louis was to join us at New Orleans, and it is too late now to change his plans."

Mona's face fell at this unexpected and disagreeable intelligence.

The last thing she desired was Louis Hamblin's companionship, and she would have been only too glad to return at once to New York.

"Could you not telegraph to him?" she suggested.

"No; for I suppose he has already left New York," Mrs. Montague curtly replied.

Mona was quite unhappy over the prospect before her; then it suddenly occurred to her that perhaps Detective Rider would need her as a witness, if he should arrest the Waltons, and in that case she would be compelled to return to New York.

Still she felt very uncomfortable even with this hope to encourage her, and but for the discovery of that morning, she would have regretted having consented to accompany Mrs. Montague upon her trip.

She sat down to mend the gloves, with what composure she could a.s.sume, although her nerves were in a very unsettled state, for she was continually looking for a summons from Mr. Rider.

When they were finished she helped about the packing of Mrs. Montague's wardrobe, and then repaired to her chamber, to get her own in readiness to leave; but still no word from the detective, and she thought it very strange.

It might have been an hour after Mona's return to the hotel, when that official sauntered into the office, where he picked up a paper and looked it over for a few minutes. Then he went to the counter, pulled the register before him, and began to glance up and down its pages.

He finally found the names he was searching for, then turning to the clerk, he requested that a boy might take a note from him to Mrs. J.M.

Walton's room.

"Mrs. Walton?" repeated the clerk, with some surprise.

"Yes; I have a little matter of business with her," said Mr. Rider, who intended to make his arrest very quietly.

"I am sorry you did not come earlier, then," regretfully responded the clerk, "for Mrs. Walton and her son left the hotel about two hours ago,"

The detective's heart sank with a sudden shock.

Gone! his birds flown when he had them so nearly captured!

"Are you sure?" he sharply demanded, while in spite of his long and severe training, he turned very white, and his under lip twitched nervously.

"Certainly, or I should not have so stated," returned the clerk, with some dignity. "When young Mr. Walton settled his bill, he ordered a carriage to be in waiting at eleven o'clock, and both he and his mother left the house at that time. I regret your disappointment, sir, in missing them."

This was almost more than Mr. Rider could bear; but he could not doubt the man's word, and he feared the thieves had escaped him again. They must have left while Mona was telling him her story at the detective headquarters.

They had been very sharp. Finding themselves in a bad box, they had planned their movements with great cunning. He believed that Mrs. Walton had deposited the amount required for bail in the bank, with the deliberate intention of forfeiting it, rather than have her accomplice brought to trial; doubtless he was too useful to her to run any risk of his being found guilty, and imprisoned for a term of years, and thus put an end to their successful career.

The detective berated himself soundly again for not objecting to the acceptance of bail at all, but it was too late now to remedy the matter.

Regrets were useless, and he must bestir himself, strike a fresh trail, if possible, and hope for better results.

He wondered why they had not skipped immediately after Jake Walton's release, but finally concluded that they had remained in the city for a day or two to disarm suspicion.

"Where did they go?" he inquired, as soon as he could command his voice to speak calmly.

"To the Grand Union Station. I believe they were going North, for I heard the young man say something about purchasing tickets, at reduced rates, for Chicago," the clerk replied.

"Had they baggage with them?" Mr. Rider questioned.

"Yes, a trunk and a good-sized grip," said the man.

The detective thought a moment.

Then he called for writing materials, hastily wrote a few lines, which he sealed, and directed to "Miss Richards."

"There is a young lady by that name stopping here, I believe," he remarked, as he laid the envelope before the clerk.

"Yes; she is with a Mrs. Montague."

"That is the lady," said the detective. "Will you see that this letter is given into her own hands, and _privately_? It is a matter of importance."

"Yes, sir, I will myself attend to the matter," responded the obliging clerk.

Mr. Rider deposited a piece of silver upon the envelope, touched his hat, and walked briskly from the hotel.

He jumped into a carriage that was waiting before the door.

"To the Grand Union Station," he ordered. "Be quick about it, and you shall have double fare."

The man was quick about it, but the train for Chicago had been gone some time.

Mr. Rider had of course expected this, but he at once sought an interview with the ticket agent, and made earnest inquiries regarding those who had purchased tickets for Chicago that morning; but he could learn of no persons answering to the description of the miner and his supposed mother.

If he could have obtained any intelligence regarding them, he had intended to telegraph ahead, and order their arrest when they should arrive at the end of their journey. But of course it would be of no use to put this plan into execution now, as he doubted very much their having gone to Chicago at all.

He was very much disheartened, and retraced his steps to his hotel, with a sickening sense of total defeat.

"Tom Rider," he muttered, fiercely, as he packed his own grip to take the first train back to New York, "you might as well give up the business and take up some trade; you've been hoodwinked by these clever thieves often enough."

But there was a very dogged, resolute expression on his plain face, nevertheless, as he turned it northward, which betrayed that he did not mean to give up his search quite yet.

That afternoon when Mona went down to dinner, the clerk of the hotel waylaid her and quietly slipped an envelope into her hand.

"Thank you," she said, in a low tone, and hastily concealed it in her pocket.

When she was alone again she broke it open and read, with almost as much disappointment as the detective himself had experienced, when he found that his birds had flown, these words:

"Gone! They gave us the slip about eleven o'clock. Save the sc.r.a.p of cloth--it may be needed later. R."

"Oh, dear!" sighed Mona, regretfully; "and the Palmer robbery is still as much of a mystery as ever."