dog, of the much-admired, white-silk variety, was barking vigorously at the Fire Bird on account of the danger to which it had been subjected by the fat tires. And the dog's mistress, Mrs. Broadbent, nicknamed "Brocade" on account of her weakness for old-time silks and satins, was saying things about the auto party in much the same sort of aggrieved tones that the favorite dog was using.

"Wait until she meets you at the post-office," Nat reminded Ned. "Maybe she won't rustle her silks and satins at you."

But Ned only laughed, and kept on laughing as his mother appeared in the vestibule with a puzzled look at the empty seat in the tonneau of the Fire Bird.

Dorothy was the first to reach the porch.

"She didn't come," was her wholly unnecessary remark as Mrs. White opened the outer door.

"Isn't that strange!" replied the aunt. "Do you suppose anything could have happened?"

"I don't know. I hope not. She promised so definitely that I can't understand it," went on Dorothy.

Nat remained in the car as Ned drove it to the garage.

"I'm so sorry, after all the extra trouble to get up a good dinner," apologized Dorothy as she laid aside her wraps.

"Oh, well, we can all enjoy that," replied Mrs. White, "although, of course, we had counted on Tavia's presence. She is so jolly that the boys will be much disappointed."

"I'm just ashamed of her," went on Dorothy in a burst of indignation. "She should have learned by this time to keep her word, or else send some message."

"Yes, I am afraid Tavia does not care for the conventionalities of polite society," remarked Mrs. White. "In fact, I almost suspect she enjoys disregarding them. But never mind! we must not condemn her unheard."

CHAPTER II

WHAT HAPPENED TO TAVIA

It must not be understood that Nat was a very silly boy. Not at all. He did like Tavia, but he liked his own sweet cousin Dorothy, and would have been just as disappointed, if not more so, had it been Dorothy who had missed her train and not Tavia.

But the fact that all seemed to need Tavia to finish up the holiday plans, and that now she had not come put Nat in a very restless mood, and when the dinner, which was served immediately upon the return from the depot, was over, Nat decided he would find something to do that would occupy his time until the eight o'clock train, when, of course, they would again go to the station.

Electricity was this young man's "hobby," and he had already fitted up the cellar with all sorts of wires and attachments for regulating the household affairs, such as turning on the heat by touching a button in the stable where the hired man, John, had his quarters, and lighting the gas in the coal-cellar by touching a button at the cook's elbow; in fact, Nat really did arrange a number of most convenient contrivances, but the family, all except Joe and Roger, thought his talent misapplied. They insisted he ought to study "railroading."

"Or laying pipes," Ned would tell him when Nat pointed out some improvement in the miniature telephone system.

But Joe and Roger loved to watch their big cousin make the sparks and turn on the signals, the latter task always being assigned to Roger, who had a very small engine of his own to practice on.

"Come on, boys," said Nat to the youngsters, when, dinner being over, Major Dale and his sister, Mrs. White, went to "figure out Christmas secrets," and Dorothy turned to the piano to put in her time until the hour for going out again, "come on, and we'll rig up something."

Instantly both little fellows were at Nat's heels, through the back hall to the cellar-way, where Nat stopped to don his overalls, for he always insisted that the first principle of true mechanics was "good, stout overalls."

Nor were the clothes protectors unbecoming to Nat. In fact, he looked the ideal workman, except he was not exactly of the muscular build, being decidedly tall, and having such a crop of light, bushy hair.

"I'll show you how to make gas," said Nat as his two young cousins waited impatiently to hear the program announced. "We can produce a very superior article by the mere use of bark from a white birch tree, and a common clay pipe. You cut the bark up into little pieces with a pair of scissors, fill the bowl of the pipe, and then make a cover or plug for the bowl by using clay or a mixture of salt, ashes and water. Stick the bowl of the pipe in the stove or furnace like this," and he opened the door of the big heater; "the fire causes the birchbark to give off a gas, it comes up into the pipestem, and can be lighted at the end, thus——"

"What was that?" interrupted Joe. "A wagon outside?"

"Might be," admitted Nat, "but what's that got to do with making birchbark gas?"

"I thought I heard some one call," apologized Joe, again taking his place in front of the heater.

"There is some one calling," declared little Roger. "I just heard them."

"Well, I guess we had better give up the gas business," said Nat impatiently, "and you kids might as well go out and interview the night air." And with this he threw down the long-stemmed pipe, which broke into a dozen pieces. Then, while the younger boys made their way back to the kitchen, Nat started for the yard.

"My, it's cold!" he could not help exclaiming as he stepped out into the clear, frosty air.

Then he brushed against something.

"It's a wonder you wouldn't knock me down!" came a voice, struggling between cold and laughter.

"Tavia!" he gasped, recognizing the tones in spite of the chattering teeth and the forced laughter.

"Yes, it's yours truly, Nat. And for gracious' sake, do let me in. What isn't frozen is paralyzed."

"Where in the world did you come from?" asked the astonished boy as he led the way to the side door.

"From some place too dark for the earth and too cold for—any other place. I think, it must have been Mars," Tavia finished, "and Mrs. Mars forgot to light the lamps."

"But there was no train," remarked Nat, waiting for some one from within to open the door in answer to his hasty knock.

"As if I didn't know that, Mr. White," replied Tavia saucily. "Do you suppose I am the kind of girl who rides in a dump-cart in preference to taking a red plush seat in a train?"

By this time the commotion had been heard, and the door was opened by almost the entire family.

"Mercy sakes!" exclaimed Dorothy, dragging Tavia in bodily.

"No mercy about it," objected Tavia, giving Dorothy a peremptory hug. "I'm simply dead and buried, without insurance. Frozen stiff, and disjointed in every limb. Why, I rode here in a dump-cart!"

"Let the girl sit down," interrupted Major Dale, who left his armchair to welcome Tavia. "My, but you are cold! No, don't go too near the fire. Sit here on the couch. Children, run off and fetch a hot drink," he added, for he saw that Tavia was indeed too cold to be safe from possible harmful consequences.

Tavia dropped into the offered seat, and then she saw Nat—in the light.

"Glory be!" she exclaimed, staring at his costume, which he had entirely forgotten. "Is it the plumber?"

"Gas man!" sang out Roger gleefully. "We had just turned the meter on when we heard your noise outside."

Nat was not proud, but he had not calculated on being in overalls when he met Tavia. Ned nearly went in kinks at his brother's discomfiture. Dorothy and Mrs. White had hurried off to fetch warm drinks for Tavia.

"You'll have to get up a 'visitor alarm,' I guess, Nat," said Joe, noting Tavia's plight and Nat's embarrassment. "If we had heard the dump-cart on the drive we would not have kept her so long out in the cold."

"That's right," answered Nat; "we will surely have to rig up something to send signals from the gate."

"Like the coal office