O Miss Ralston, will you ride horseback with me this morning instead of going over in the coach to see the geysers?" An unfamiliar masculine voice spoke near Jack. She had stolen out of doors early to catch a view of "The Sleeping Giant," one of the natural curiosities of Yellowstone Lake, the perfect outline of a human face turned skyward reflected in one of the pools near the hotel. Jack started and turned to discover Mr. Drummond.

"I brought my own horses to the Yellowstone with me," he continued, "and I am sure you will find riding more agreeable than being bounced around in a rickety coach. I heard your chaperon say last night that you intended to give your own horses and caravan a rest. We can ride near enough the stage for them to look after you."

Jack's eyes sparkled with pleasure, like a child's. "Oh, please, do you really wish me to ride with you?" she asked, only half convinced. "One of the girls I met at the hotel yesterday told me you had the most wonderful horses. But how did you ever guess how I loved to ride?"

Mr. Drummond laughed. Jack's acceptance of his invitation was as frank as a boy's. She made no pretense of caring for Mr. Drummond's society as she did for the chance to ride.

"It is easy enough to guess you can ride or do anything else that belongs to the outdoors," he returned smiling. "So please don't forget to ask your chaperon right away, so I can give my man the order for our horses."

Jack nodded happily. "Oh, I am sure it will be all right," she answered. "I hope you won't think we are very unconventional, but you see we have always lived on a ranch, and perhaps we don't know all the fine social distinctions, just what's right and what's wrong for a girl to do." She laughed cheerfully. Nothing in the wide world interested Jack less than society, and never could she have become such good friends with Peter if she had met him anywhere else than here in the wilderness. Jack had none of the stirrings of sentiment in her, but although she was a young girl and Mr. Drummond a man of wide experience she had a genius for friendship, which he was to find out in an amazingly short time.

An hour later a dozen or more people trooped out of the hotel ready for the day's amusement. It had been arranged that the Harmons and the caravan party should drive over to the most reliable geyser in the Yellowstone Park, "Old Faithful," who pours forth his steaming, scalding water every seventy minutes as regularly as clock work. Fortunately for the ranch girls, Ruth had seen that each one of them owned a second traveling costume, for the outfits in which they left Rainbow Ranch were too dilapidated to put on again. Now they appeared in new khaki costumes, looking as fresh and businesslike as the day they first set out on their journey. Only Jack wore a corduroy riding habit.

Olive and Jack gazed with open admiration at Mrs. Harmon, never having seen a woman so beautifully gowned before. Somehow in her soft, hunter's green broadcloth and close-fitting hat she did suggest Olive—Jack thought, perhaps because she wore Olive's favorite shade of green.

Ralph Merrit had waited to say a final good-by to the caravan party just before the stage rolled away. He had walked over with Jack to where Mr. Drummond and his groom waited with the horses; then he came back, kissed Frieda and shook hands with Olive, Ruth and Jim. Jean was looking everywhere but in his direction.

She held a small book in her hand, and Ruth looked at it curiously. Jean was fond of reading, but she would hardly select the day they were to visit the most famous geyser in the world to pursue her literary tastes. Sticking forth from the pages, quite by accident Ruth saw a spray of pale blue forget-me-nots; they grew everywhere about the park.

"You'll be sure to come to Rainbow Lodge to see us some day, won't you?" Ruth urged cordially. Jim gave Ralph's hand another shake. "We'll count on you," he urged. "You know I told you I never liked a fellow half so well in so short a time."

"Won't you say good-by, Jean, and take back what you said last night?" Ralph asked, half serious and half smiling.

Jean thrust out a book. "I suppose I must," she answered, "as I hate to be cross with people when they are so far away there is no chance to quarrel. I have put a spray of forget-me-nots in this book, so you won't forget us," she ended prettily.

Just before the coach moved off Jack, mounted on a thoroughbred horse, rode up to show herself to her friends with Mr. Drummond following behind her.

In the best seat in the stage, with sofa cushions piled about her, sat Elizabeth Harmon. As she saw Jack an ill-humored expression crossed her face. "I thought we were going to have the drive together. You promised only last night that you would try to make me have a good time, and now first thing next morning you are going off and leaving me," she exclaimed.

Jack turned crimson. She had meant to be good to Elizabeth, but it had never occurred to her to give up her horseback ride on her account.

"I am sorry, Elizabeth," she answered uncomfortably. "Perhaps Mr. Drummond would exchange me for Jean or Olive. I didn't know you cared so much about my driving with you."

Jean and Olive both shook their heads decidedly, and Frieda gazed at Elizabeth in stern disapproval; but Mr. Drummond, who was also accustomed to having his own way, settled the matter. "You'll take the ride with me this morning, Miss Ralston," he announced, "then you can devote yourself to your friend later in the day if you like." And Elizabeth was obliged to be content.

Jack was convinced she had never had such a wonderful ride in her life, never had she felt in such glorious health and spirits. Her horse moved along under her with a gait to which she was entirely unaccustomed. Only shaggy bronchos and rough western ponies had been her mounts until to-day, and now she was on the back of a beautiful Kentucky thoroughbred, riding over a perfect road, very different from the long stretches of sand on the plains. The two riders had galloped on for several miles without a word, Peter keeping a little in the background to enjoy the wonderful grace and ease of Jack's horsemanship.

Suddenly the girl reined in her horse and the man slowed down. "I want to thank you for this glorious ride now while I have the chance," she said simply. "Sometimes I wish I could spend my whole life in the saddle, I love it so. I hope I wasn't selfish in not driving with Elizabeth Harmon. I am so horribly sorry for people who can't ride and walk and swim and enjoy the things I do, I would do nearly anything in the world for them," she ended wistfully. And for a long time afterward Mr. Drummond remembered what Jack had said and her beauty and careless vigor as she spoke, with her hands holding her mare's reins lightly but firmly and her body keeping perfect rhythm with its every movement.

The two riders came to the neighborhood of the great geyser a little in advance of the coaching party. They rode up to within a reasonable distance of the queer, symmetrical, cone-shaped hill. There were a few people waiting about, but the place was quite peaceful and showed no sign of the leaping torrent of water Jack anticipated. She was intending to dismount from her horse when the stage arrived. Suddenly a roar, like a giant's snort, came from beneath the earth and almost instantly steaming water began to rise through the mouth of the cone in glistening, gleaming bubbles, then a giant cataract reared itself. Jack and Peter Drummond had been too surprised at the geyser's sudden display of its powers to get off their horses at once, and Jack's thoroughbred was not trained to endure any such exhibition of the unknown forces of nature. Her whole body quivered as though she had been struck a cruel blow, then, making a leap straight into the air and coming down on her two hind feet, she began to dance and curvet and leap about as though bewitched. Mr. Drummond had a horrified moment of fearing Jack would be dreadfully injured, but he was too engaged in quieting his own horse's terror to give her aid. The coaching party arrived on the scene at this minute and they were torn between interest in the marvelous geyser and concern for Jack's safety.

Jack proved her horsemanship by recognizing that the high-strung animal she was riding required a different treatment from one of her rough ponies. Never once did she use her whip on the pretty mare, but talked to her in a gentle, soothing tone, keeping her nose turned directly toward the roaring stream of water, so that the mare should not bolt and run on hearing extraordinary noises at her back.

In four or five minutes two hundred and fifty thousand gallons of scalding water had been raised one hundred and fifty feet in the air, held for a little time and then dashed down to earth again, and "Old Faithful" was once more peaceful for exactly an hour and ten minutes.

But in this period Jacqueline had brought her horse to a quivering standstill not far from the geyser. Elizabeth Harmon was pale with fright and her eyes were full of tears of apprehension, but Frieda was merely interested in her sister's performance, as she had not the least idea of her being hurt.

In a few seconds after the excitement had passed, Jim Colter leapt out of the stage and walked toward Jack. "Bravo!" he said, as she slid off her mare, handing her reins to Mr. Drummond.

"I beg your pardon, sir," he continued stiffly—Mr. Drummond's citified elegance had irritated him—"I couldn't help feeling some pride in Miss Ralston's cool head. When it comes to a question of nerve, Jack, you certainly have got the right stuff in you," he concluded. And Jack blushed happily, because Jim's praises were rare, not caring half so much that her new friend was even more impressed by her courage than her old one.