That night Dr. Fenton had a visitor. We know that visitor and we almost know what his questions were, if not the answers of the good doctor. Nevertheless, it may be better to listen to a part at least of their conversation. Sweetwater, who knew when to be frank and open, as well as when to be reserved and ambiguous, made no effort to disguise the nature of his business or his chief cause of interest in Oswald Brotherson. The eye which met his was too penetrating not to detect the smallest attempt at subterfuge; besides, Sweetwater had no need to hide his errand; it was one of peace, and it threatened nobody—“the more’s the pity,” thought he in uneasy comment to himself, as he realised the hopelessness of the whole situation.

His first word, therefore, was a plain announcement.

“Dr. Fenton, my name is Sweetwater. I am from New York, and represent for the nonce, Mr. Challoner, whose name I have simply to mention, for you to understand that my business is with Mr. Brotherson whom I am sorry to find seriously, if not dangerously, ill. Will you tell me how long you think it will be before I can have a talk with him on a subject which I will not disguise from you may prove a very exciting one?”

“Weeks, weeks,” returned the doctor. “Mr. Brotherson has been a very sick man and the only hope I have of his recovery is the fact that he is ignorant of his trouble or that he has any cause for doubt or dread. Were this happy condition of things to be disturbed,—were the faintest rumour of sorrow or disaster to reach him in his present weakened state, I should fear a relapse, with all its attendant dangers. What then, if any intimation should be given him of the horrible tragedy suggested by the name you have mentioned? The man would die before your eyes. Mr. Challoner’s business will have to wait.”

“That I see; but if I knew when I might speak—”

“I can give you no date. Typhoid is a treacherous complaint; he has the best of nurses and the chances are in favour of a quick recovery; but we never can be sure. You had better return to New York. Later, you can write me if you wish, or Mr. Challoner can. You may have confidence in my reply; it will not mislead you.”

Sweetwater muttered his thanks and rose. Then he slowly sat down again.

“Dr. Fenton,” he began, “you are a man to be trusted. I’m in a devil of a fix, and there is just a possibility that you may be able to help me out. It is the general opinion in New York, as you may know, that Miss Challoner committed suicide. But the circumstances do not fully bear out this theory, nor can Mr. Challoner be made to accept it. Indeed, he is so convinced of its falsehood, that he stands ready to do anything, pay anything, suffer anything, to have this distressing blight removed from his daughter’s good name. Mr. Brotherson was her dearest friend, and as such may have the clew to this mystery, but Mr. Brotherson may not be in a condition to speak for several weeks. Meanwhile, Mr. Challoner must suffer from great suspense unless—” a pause during which he searched the doctor’s face with a perfectly frank and inquiring expression—“unless some one else can help us out. Dr. Fenton, can you?”

The doctor did not need to speak; his expression conveyed his answer.

“No more than another,” said he. “Except for what Doris felt compelled to tell me, I know as little as yourself. Mr. Brotherson’s delirium took the form of calling continually upon one name. I did not know this name, but Doris did, also the danger lurking in the fact that he had yet to hear of the tragedy which had robbed him of this woman to whom he was so deeply attached. So she told me just this much. That the Edith whose name rung so continuously in our ears was no other than the Miss Challoner of New York of whose death and its tragic circumstances the papers have been full; that their engagement was a secret one unshared so far as she knew by any one but herself. That she begged me to preserve this secret and to give her all the help I could when the time came for him to ask questions. Especially did she entreat me to be with her at the crisis. I was, but his waking was quite natural. He did not ask for Miss Challoner; he only inquired how long he had been ill and whether Doris had received a letter during that time. She had not received one, a fact which seemed to disappoint him; but she carried it off so gaily (she is a wonderful girl, Mr. Sweetwater—the darling of all our hearts), saying that he must not be so egotistical as to think that the news of his illness had gone beyond Derby, that he soon recovered his spirits and became a very promising convalescent. That is all I know about the matter; little more, I take it, than you know yourself.”

Sweetwater nodded; he had expected nothing from the doctor, and was not disappointed at his failure. There were two strings to his bow, and the one proving valueless, he proceeded to test the other.

“You have mentioned Miss Scott, as the confidante—and only confidante of this unhappy pair,” said he. “Would it be possible—can you make it possible for me to see her?”

It was a daring proposition; he understood this at once from the doctor’s expression; and, fearing a hasty rebuff, he proceeded to supplement his request with a few added arguments, urged with such unexpected address and show of reason that Dr. Fenton’s aspect visibly softened and in the end he found himself ready to promise that he would do what he could to secure his visitor the interview he desired if he would come to the house the next day at the time of his own morning visit.

This was as much as the young detective could expect, and having expressed his thanks, he took his leave in anything but a discontented frame of mind. With so powerful an advocate as the doctor, he felt confident that he should soon be able to conquer this young girl’s reticence and learn all that was to be learned from any one but Mr. Brotherson himself. In the time which must elapse between that happy hour and the present, he would circulate and learn what he could about the prospective manager. But he soon found that he could not enter the Works without a permit, and this he was hardly in a position to demand; so he strolled about the village instead, and later wandered away into the forest.

Struck by the inviting aspect of a narrow and little used road opening from the highway shortly above the house where his interests were just then centred, he strolled into the heart of the spring woods till he came to a depression where a surprise awaited him, in the shape of a peculiar structure rising from its midst where it just fitted, or so nearly fitted that one could hardly walk about it without brushing the surrounding tree trunks. Of an oval shape, with its door facing the approach, it nestled there, a wonder to the eye and the occasion of considerable speculation to his inquiring mind. It had not been long built, as was shown very plainly by the fresh appearance of the unpainted boards of which it was constructed; and while it boasted of a door, as I’ve already said, there were no evidences visible of any other break in the smooth, neatly finished walls. A wooden ellipse with a roof but no windows; such it appeared and such it proved to be. A mystery to Sweetwater’s eyes, and like all mysteries, interesting. For what purpose had it been built and why this isolation? It was too flimsy for a reservoir and too expensive for the wild freak of a crank.

A nearer view increased his curiosity. In the projection of the roof over the curving sides he found fresh food for inquiry. As he examined it in the walk he made around the whole structure, he came to a place where something like a hinge became visible and further on another. The roof was not simply a roof; it was also a lid capable of being raised for the air and light which the lack of windows necessitated. This was an odd discovery indeed, giving to the uncanny structure the appearance of a huge box, the cover of which could be raised or lowered at pleasure. And again he asked himself for what it could be intended? What enterprise, even of the great Works, could demand a secrecy so absolute that such pains as these should be taken to shut out all possibility of a prying eye. Nothing in his experience supplied him with an answer.

He was still looking up at these hinges, with a glance which took in at the same time the nearness and extreme height of the trees by which this sylvan mystery was surrounded, when a sound from the road on the opposite side of the hollow brought his conjectures to a standstill and sent him hurrying on to the nearest point from which that road became visible.

A team was approaching. He could hear the heavy tread of horses working their laborious way through trees whose obstructing branches swished before and behind them. They were bringing in a load for this shed, whose uses he would consequently soon understand. Grateful for his good luck—for his was a curiosity which could not stand defeat—he took a few steps into the wood, and from the vantage point of a concealing cluster of bushes, fixed his eyes upon the spot where the road opened into the hollow.

Something blue moved there, and in another moment, to his great amazement, there stepped into view the spirited form of Doris Scott, who if he had given the matter a thought he would have supposed to be sitting just then by the bedside of her patient, a half mile back on the road.

She was dressed for the woods in a blue skirt and jacket and moved like a leader in front of a heavily laden wagon now coming to a standstill before the closely shut shed—if such we may call it.

“I have a key,” so she called out to the driver who had paused for orders. “When I swing the doors wide, drive straight in.”

Sweetwater took a look at the wagon. It was piled high with large wooden boxes on more than one of which he could see scrawled the words: O. Brotherson, Derby, Pa.

This explained her presence, but the boxes told nothing. They were of all sizes and shapes, and some of them so large that the assistance of another man was needed to handle them. Sweetwater was about to offer his services when a second man appeared from somewhere in the rear, and the detective’s attention being thus released from the load out of which he could make nothing, he allowed it to concentrate upon the young girl who had it in charge and who, for many reasons, was the one person of supreme importance to him.

She had swung open the two wide doors, and now stood waiting for horse and wagon to enter. With locks flying free—she wore no bonnet—she presented a picture of ever increasing interest to Sweetwater. Truly she was a very beautiful girl, buoyant, healthy and sweet; as unlike as possible his preconceived notions of Miss Challoner’s humble little protegee. Her brown hair of a rich chestnut hue, was in itself a wonder. On no head, even in the great city he had just left, had he seen such abundance, held in such modest restraint. Nature had been partial to this little working girl and given her the chevelure of a queen.

But this was nothing. No one saw this aureole when once the eye had rested on her features and caught the full nobility of their expression and the lurking sweetness underlying her every look. She herself made the charm and whether placed high or placed low, must ever attract the eye and afterwards lure the heart, by an individuality which hardly needed perfect features in which to express itself.

Young yet, but gifted, as girls of her class often are, with the nicest instincts and purest aspirations, she showed the elevation of her thoughts both in her glance and the poise with which she awaited events. Sweetwater watched her with admiration as she superintended the unloading of the wagon and the disposal of the various boxes on the floor within; but as nothing she said during the process was calculated to afford the least enlightenment in regard to their contents, he presently wearied of his inaction and turned back towards the highway, comforting himself with the reflection that in a few short hours he would have her to himself when nothing but a blunder on his part should hinder him from sounding her young mind and getting such answers to his questions as the affair in which he was so deeply interested, demanded.