Despite Smiles' ingenuous proffer of a sister's affection, Donald was troubled with an unreasonable dissatisfaction over the course which the events of the morning had taken, and he knew that it was unreasonable, which made it worse. Now he suddenly announced that he guessed he would not wait until the afternoon before going down to Fayville to get his small amount of baggage.

The girl was troubled, also, without knowing just why, and she watched his departure with an unhappy feeling that somehow the changes which the year had made in both their lives had raised a misty barrier between them—intangible, but not easily to be swept away. Furthermore, young as she was, she intuitively sensed that hers was the necessity of reconstructing their friendship on a new foundation, because she was a woman. The man could not do it.

Meanwhile Donald performed his downward journey with none of the lightness of heart which makes a long walk a pleasure, rather than a task. Going down the wooded descent, where the dew still lay wet beneath the heaviest thickets, was not so bad; but, when he had obtained his grip and gun, and started on the back trail, his discomforts commenced. As the main street of the little village changed its character, first to a road and then a cart path through the fields, it grew deep with dust, and, although no air stirred, it seemed to rise, as water does by capillary attraction, until his clothing was saturated and his mouth and nose overlaid with a film of it. Overhead the sky burned, and from the brown fields, which stretched to the wooded base of the mountain, heat waves rose as though the dry earth were panting with visible breath. An insect chirped half-heartedly in the grass, and then left off as though the effort were too great, and a small striped snake leisurely wove a sinuous path through the dust ahead of him, and vanished with a faint hiss.

It was better when he struck the woods, for there was shade; but the air was more sultry and the added exertion of climbing started the perspiration and turned the coating of dust to sticky grime. Still the breeze delayed, and the fragrant odors of the woods were cloying. His luggage grew heavier and yet more heavy; his arm and back began to ache painfully.

When physical discomfort is accompanied by morose introspection, the result is certain to be unpleasant, and Donald's thoughts were in dismal grays and browns, which ill-matched the radiant colors of external nature.

Certainly Smiles was not to blame, he thought, as he trudged up and up. The fact still remained that they lived on utterly different planes, and that he had not the slightest idea of falling in love with her, or, even mentally, violating his pledge to Marion. Pshaw, she was nothing but a child! It was foolish, absurdly so, yet somehow he felt that his world was out of joint, and, since he could not, or would not, determine just what the trouble was, he could not take active measures to bring about a readjustment.

With a conscious effort of his will he put the mountain child out of his thoughts, and attempted to analyze his real feelings for the city girl, to whom he was betrothed. He could assign no reason to the vague, but persistent, feeling which frequently possessed him, when he was apart from her, that she was not his natural mate. Her poise and reserve, which sometimes irritated him, he knew to be really virtues, in a way as desirable as they were rare in women, even of her class; her unusual beauty fully satisfied his eye; she was a reigning queen, the desired of many men and he had won her, although he hesitated a little over the word "won." Finally, he was certain that she loved him, after her fashion. Why should he, a man as reserved as he was, and one who had little time to spend on the romantic embellishments of life, ask for more? Yet there was mute rebellion in the depths of his heart, and even the memory of that milestone night, eight months before, when the spirit of Christmastide had added its spell to the influences of life-long propinquity, and they had, almost without spoken words, crossed the border and pledged themselves to one another, brought no thrill.

"I know that she is a wonderful woman, and a real beauty," mused Donald, half aloud. "The trouble must be ... yes, is, with me. She's too wonderful for my simple tastes; that's the truth, as I told Ethel. Oh, well, perhaps I can learn to live up to her ... but I hate this society stuff."

Donald's return to the cabin, weary and uncomfortable in body and mind, found Big Jerry sitting heavily in a chair, with Smiles hovering about, and, from the expression on the face of each, he sensed at once that something was wrong. The old man was saying, somewhat laboriously, "Hit don't pain me ... much, Rose, gal. Hit haint nothin' ... ter mention. I'll jest set still hyar erwhile, an' ..."

As the girl caught sight of Donald's big form in the doorway, her face brightened momentarily; but it clouded again with swift pain when he touched his heart with a significant gesture, accompanied by a questioning look. She nodded, then said aloud, "Here's our Doctor Mac back ergin, grandpappy. I reckon he kin do somethin' fer ter help ye."

The newcomer attempted a cheery laugh, and said, "Well, I'm not much good unless we can turn Time's flight backward, and make him a child again temporarily. Kiddies are my specialty, you know, and although I've a few grown-up patients, left over from the time when I took whatever came, and was thankful, I am killing them off as fast as I can."

He spoke facetiously, with the design of instilling a lighter element in the conversation; but, although Jerry smiled wryly, the girl looked so shocked that Donald hastened to add, "Please don't be alarmed, dear, of course I didn't mean that literally. And you know that I will do anything in my power to help. I only wish that I knew more about troubles affecting the heart," he added.

"Reckon the doctor down in Fayville hed ought ter say the same thing," interposed the old man. "I erlows he didn't do me no good, fer I got better es soon's I quit takin' the stuff he left me."

"Don't be too hard on him, foster father. After all, what you probably needed most was to give that big heart of yours a rest, and that is what did the business then, and will now. Well, I'll look you over anyway. I guess professional ethics won't be outraged, with the other physician five steep, uphill miles away."

While he talked he had been opening his suitcase, and now took out a compact emergency bag which experience had taught him never to go away without, and at whose shining, unfamiliar contents Smiles' eyes opened with fascinated amazement. Taking out a stethoscope, Donald bade the giant open his soft, homemade shirt, and planted the transmitting disk against the massive chest, padded with wonderful, bulging muscles.

"O-ho," he said under his breath, as he finally laid the instrument aside; for his intently listening ears had caught the faint, but clearly discernible sound of a systolic murmur, deep within.

"Air the trouble 'Aunt' ... what the other doctor said hit was?" questioned Rose.

"Angina pectoris? He may have had a touch of that last winter of course, but my guess is that it's something a bit different now."

"I haint erfeered ter hyar the truth," rumbled Jerry, straightening up like a soldier before the court martial.

"Well," answered the doctor, "I should say that you have a touch of another jaw-breaking Latin phrase, namely, an aneurism of the thoracic aorta."

"Hit shor' sounds powerful bad," grunted Jerry. "But then I reckon thet doctors likes ter use big words."

"Right. For instance, we prefer to call an old-fashioned cold in the head, 'Naso-pharyngitis.' The worse it sounds, the more credit we get for curing it, you see. Well, 'sticks and stones may break our bones, but words will never hurt us,' so don't let that Latin expression worry you. Just take things a bit easy, don't overdo physically or get overexcited, and you'll be good for many a moon yet," he added lightly.

Jerry fastened up his shirt with big, fumbling fingers and walked slowly outside, while Rose, tears of pity shedding a misty luminousness over her eyes, stepped close to Donald and laid her hand appealingly on his arm, "Is it something pretty bad, Doctor Mac?" she breathed.

"Well, it's apparently a mild case ... so far."

"But the trouble ... is it ... is it dangerous?"

He hesitated an instant, then responded quietly, "Nurses have to know the truth, of course, and I am sure that you have a brave little heart, so I'm not afraid to tell you that it is bad. It is almost sure to be fatal, in time, but not necessarily soon. If he will take things easy, as I told him to, he'll live for a considerable time yet; but we mustn't allow him to get very greatly excited, or do any very heavy work."

Suddenly very white, but calm and tearless, Smiles answered, "I reckon I can help him better if I know all about it, doctor. I got to help him, you know. He's all I have now in the whole world."

"Of course you're going to help him—we both are—but ... you have me, little sister, and your life work," he answered with awkward tenderness. "Now let us see if I can make you understand what I believe the trouble to be. In its incipient—that is, its early stages, it would be rather hard to tell from angina pectoris, for the symptoms would be much the same—pain about the heart and shortness of breath. But one can get over the latter, and feel perfectly well between attacks."

He picked up from his open suitcase a folded newspaper which he had tossed in half read, on leaving the city, and drew for her a crude diagram of the heart and major arteries.

"This biggest pipe which goes downward from the heart is called the great artery, and it and its branches—just like a tree's—carry the blood into all parts of the body, except the lungs. Another name for it is the descending thoracic aorta, and that is where grandfather's trouble is. If you knew something about automobile tires I would explain it by saying that he had a blow-out, but it's something like this. The pipe has an outer surface and an inner lining. At one time or another something happened to injure and weaken the former—disease does it sometimes—perhaps it may have been a severe strain or crushing blow on his chest."

"A big tree fell on him early last winter," cried Rose, with sudden enlightenment. "His chest is so big and strong that he didn't think that it hurt him, 'cept to lame him considerable."

"That may have caused the trouble. Well, what happens is this. The blood is pumped by the heart through that weakened pipe, and, little by little, it forces the lining out through the weakened spot, making something like a bubble filled with blood. In time that might grow until you could actually see the swelling, and all the time, the containing tissue is getting thinner and thinner. Now you can yourself guess the reason why he mustn't do anything to over-exert his heart. Hard work, or great excitement, makes our hearts beat faster, and sends the blood through that big artery with extra force and ..."

"The bubble might ... break," whispered "Smiles," with a frightened look on her young face.

"Yes. We call it a rupture of the aneurism, and when that happens mortal life ends."

"Oh," she shuddered slightly. "I must keep him very quiet, Doctor Mac. I am strong and can do all the work. You tell him that he mustn't do anything, please, doctor."

"I'm not sure that that would be the wisest plan, Rose. He has been so strong and active all his life it would break his great heart to be tied down like an invalid. I'm sure that he would be happier doing things, even if as a result he didn't live quite so long. Don't you think so, yourself?"

She nodded, and he continued, "Of course he is so big and strong he can do common, simple tasks without anything like the amount of exertion required by an ordinary man, and, so long as he doesn't strain himself, or get very much excited, we may reasonably expect him to live for a good while yet. Besides, as the aneurism progresses there will come a steady, boring pain and increased shortness of breath, which will themselves help to keep him quiet."

"But can't I give him some medicine?"

"The best medicine that he can possibly have will be your happy, comforting smile and tender love, my child."

She furtively wiped a stray tear from her cheek and smiled bravely up into his face, in a wordless pledge that to the administration of this treatment she would devote herself without stint.

"May I ... may I have that paper," she answered appealingly, as he started to crumple it up, preparatory to tossing it into the fireplace. "We don't often have city papers to read, you know."

"Why, of course; I didn't think," he answered, smoothing it out and handing it to her. She took it eagerly, and had read barely a minute before she cried, delightedly, "Why, Doctor Mac. You're in this paper. Oh, did you read what it says?"

"Hang it," thought Donald, "I forgot all about that fool story, or I wouldn't have given it to her." But she was already reading the brief article aloud, slowly but with appreciatory expression.

EXCEPTIONAL FEE PAID BOSTON DOCTOR
Dr. Donald MacDonald Operates on Multi-Millionaire's
Child

What is rumored to have been one of the biggest fees paid to a physician in recent years, was received lately by the brilliant young children's specialist of this city, Dr. Donald MacDonald.