On the fourteenth of December Billy came down-stairs alert, interested, and happy. She had received a dear letter from Bertram (mailed on the way to New York), the sun was shining, and her fingers were fairly tingling to put on paper the little melody that was now surging riotously through her brain. Emphatically, the restlessness of the day before was gone now. Once more Billy's “clock” had “begun to tick.”

After breakfast Billy went straight to the telephone and called up Arkwright. Even one side of the conversation Aunt Hannah did not hear very clearly; but in five minutes a radiant-faced Billy danced into the room.

“Aunt Hannah, just listen! Only think—Mary Jane wrote the words himself, so of course I can use them!”

“Billy, dear, can't you say 'Mr. Arkwright'?” pleaded Aunt Hannah.

Billy laughed and gave the anxious-eyed little old lady an impulsive hug.

“Of course! I'll say 'His Majesty' if you like, dear,” she chuckled. “But did you hear—did you realize? They're his own words, so there's no question of rights or permission, or anything. And he's coming up this afternoon to hear my melody, and to make a few little changes in the words, maybe. Oh, Aunt Hannah, you don't know how good it seems to get into my music again!”

“Yes, yes, dear, of course; but—” Aunt Hannah's sentence ended in a vaguely troubled pause.

Billy turned in surprise.

“Why, Aunt Hannah, aren't you glad? You said you'd be glad!”

“Yes, dear; and I am—very glad. It's only—if it doesn't take too much time—and if Bertram doesn't mind.”

Billy flushed. She laughed a little bitterly.

“No, it won't take too much time, I fancy, and—so far as Bertram is concerned—if what Sister Kate says is true, Aunt Hannah, he'll be glad to have me occupy a little of my time with something besides himself.”

“Fiddlededee!” bristled Aunt Hannah.

“What did she mean by that?”

Billy smiled ruefully.

“Well, probably I did need it. She said it night before last just before she went home with Uncle William. She declared that I seemed to forget entirely that Bertram belonged to his Art first, before he belonged to me; and that it was exactly as she had supposed it would be—a perfect absurdity for Bertram to think of marrying anybody.”

“Fiddlededee!” ejaculated the irate Aunt Hannah, even more sharply. “I hope you have too much good sense to mind what Kate says, Billy.”

“Yes, I know,” sighed the girl; “but of course I can see some things for myself, and I suppose I did make—a little fuss about his going to New York the other night. And I will own that I've had a real struggle with myself sometimes, lately, not to mind—his giving so much time to his portrait painting. And of course both of those are very reprehensible—in an artist's wife,” she finished, a little tremulously.

“Humph! Well, I don't think I should worry about that,” observed Aunt Hannah with grim positiveness.

“No, I don't mean to,” smiled Billy, wistfully. “I only told you so you'd understand that it was just as well if I did have something to take up my mind—besides Bertram. And of course music would be the most natural thing.”

“Yes, of course,” agreed Aunt Hannah.

“And it seems actually almost providential that Mary—I mean Mr. Arkwright is here to help me, now that Cyril is gone,” went on Billy, still a little wistfully.

“Yes, of course. He isn't like—a stranger,” murmured Aunt Hannah. Aunt Hannah's voice sounded as if she were trying to convince herself—of something.

“No, indeed! He seems just like one of the family to me, almost as if he were really—your niece, Mary Jane,” laughed Billy.

Aunt Hannah moved restlessly.

“Billy,” she hazarded, “he knows, of course, of your engagement?”

“Why, of course he does, Aunt Hannah everybody does!” Billy's eyes were plainly surprised.

“Yes, yes, of course—he must,” subsided Aunt Hannah, confusedly, hoping that Billy would not divine the hidden reason behind her question. She was relieved when Billy's next words showed that she had not divined it.

“I told you, didn't I? He's coming up this afternoon. He can't get here till five, though; but he's so interested! He's about as crazy over the thing as I am. And it's going to be fine, Aunt Hannah, when it's done. You just wait and see!” she finished gayly, as she tripped from the room.

Left to herself, Aunt Hannah drew a long breath.

“I'm glad she didn't suspect,” she was thinking. “I believe she'd consider even the question disloyal to Bertram—dear child! And of course Mary”—Aunt Hannah corrected herself with cheeks aflame—“I mean Mr. Arkwright does—know.”

It was just here, however, that Aunt Hannah was mistaken. Mr. Arkwright did not—know. He had not reached Boston when the engagement was announced. He knew none of Billy's friends in town save the Henshaw brothers. He had not heard from Calderwell since he came to Boston. The very evident intimacy of Billy with the Henshaw brothers he accepted as a matter of course, knowing the history of their acquaintance, and the fact that Billy was Mr. William Henshaw's namesake. As to Bertram being Billy's lover—that idea had long ago been killed at birth by Calderwell's emphatic assertion that the artist would never care for any girl—except to paint. Since coming to Boston, Arkwright had seen little of the two together. His work, his friends, and his general mode of life precluded that. Because of all this, therefore, Arkwright did not—know; which was a pity—for Arkwright, and for some others.

Promptly at five o'clock that afternoon, Arkwright rang Billy's doorbell, and was admitted by Rosa to the living-room, where Billy was at the piano.

Billy sprang to her feet with a joyous word of greeting.

“I'm so glad you've come,” she sighed happily. “I want you to hear the melody your pretty words have sung to me. Though, maybe, after all, you won't like it, you know,” she finished with arch wistfulness.

“As if I could help liking it,” smiled the man, trying to keep from his voice the ecstatic delight that the touch of her hand had brought him.

Billy shook her head and seated herself again at the piano.

“The words are lovely,” she declared, sorting out two or three sheets of manuscript music from the quantity on the rack before her. “But there's one place—the rhythm, you know—if you could change it. There!—but listen. First I'm going to play it straight through to you.” And she dropped her fingers to the keyboard. The next moment a tenderly sweet melody—with only a chord now and then for accompaniment—filled Arkwright's soul with rapture. Then Billy began to sing, very softly, the words!

No wonder Arkwright's soul was filled with rapture. They were his words, wrung straight from his heart; and they were being sung by the girl for whom they were written. They were being sung with feeling, too—so evident a feeling that the man's pulse quickened, and his eyes flashed a sudden fire. Arkwright could not know, of course, that Billy, in her own mind, was singing that song—to Bertram Henshaw.

The fire was still in Arkwright's eyes when the song was ended; but Billy very plainly did not see it. With a frowning sigh and a murmured “There!” she began to talk of “rhythm” and “accent” and “cadence”; and to point out with anxious care why three syllables instead of two were needed at the end of a certain line. From this she passed eagerly to the accompaniment, and Arkwright at once found himself lost in a maze of “minor thirds” and “diminished sevenths,” until he was forced to turn from the singer to the song. Still, watching her a little later, he noticed her absorbed face and eager enthusiasm, her earnest pursuance of an elusive harmony, and he wondered: did she, or did she not sing that song with feeling a little while before?

Arkwright had not settled this question to his own satisfaction when Aunt Hannah came in at half-past five, and he was conscious of a vague disappointment as he rose to greet her. Billy, however, turned an untroubled face to the newcomer.

“We're doing finely, Aunt Hannah,” she cried. Then, suddenly, she flung a laughing question to the man. “How about it, sir? Are we going to put on the title-page: 'Words by Mary Jane Arkwright'—or will you unveil the mystery for us now?”

“Have you guessed it?” he bantered.

“No—unless it's 'Methuselah John.' We did think of that the other day.”

“Wrong again!” he laughed.

“Then it'll have to be 'Mary Jane,'” retorted Billy, with calm naughtiness, refusing to meet Aunt Hannah's beseechingly reproving eyes. Then suddenly she chuckled. “It would be a combination, wouldn't it? 'Words by Mary Jane Arkwright. Music by Billy Neilson'! We'd have sighing swains writing to 'Dear Miss Arkwright,' telling how touching were her words; and lovelorn damsels thanking Mr. Neilson for his soul-inspiring music!”

“Billy, my dear!” remonstrated Aunt Hannah, faintly.

“Yes, yes, I know; that was bad—and I won't again, truly,” promised Billy. But her eyes danced, and the next moment she had whirled about on the piano stool and dashed into a Chopin waltz. The room itself, then, seemed to be full of the twinkling feet of elves.