bath,” Mr. Anderson reminded his pupils. “You have to work fast, you know.”

Dorothy brought out her two shallow basins, one smaller than the other. The larger had its inside well greased and the smaller was thoroughly rubbed over on its under side. Into the larger they poured about an inch of concrete and then squeezed the smaller dish into it, but not so sharply that it cut through. They filled in the crack between the two, pushing and patting the mixture into place, and they smoothed the edge so that it turned over the rim of the larger bowl before they cut it off evenly all around with a wire.

The Bird’s Bath

“There,” said Mr. Anderson as he watched them. “We’ll see what will come from that. It might be better done—” at which the girls all pulled long faces—“but also, it might be worse, or I’m very much mistaken.”

“I wish we could make some garden furniture,” sighed Dorothy, holding up her dripping hands helplessly, but at the same time gazing with joy at their new manufacture.

“You could if you would make the forms,” said Mr. Anderson. “All you need to do is to make a bench inside of another bench and fill the space between with concrete.”

“That sounds easy, but if you were a girl, Mr. Anderson, you might find it a little hard to make the forms.”

“We can all drive nails,” insisted Ethel Brown stoutly. “I believe I’ll try.”

But the others laughed at her and reminded her that she would have to drive the nails through rather heavy planking, so she gave up the notion.

“What are the walls going to be made of?” Margaret asked Dorothy.

“Something fireproof, Mother said, but I don’t know what she finally decided on. I’ll ask Mr. Anderson.”

“Plaster on hollow tile,” the contractor answered absent-mindedly over his shoulder, as he walked briskly before them back to the cellar.

The girls saw that he was too full of business now to pay any more attention to them, so they thanked him for giving them so much time and made some investigations on their own account among the piles of material lying about on the grounds.

“I wonder if this could be ‘hollow-tile,’” Ethel Blue said to the rest as she came across a stack of strange-looking pieces of brown earthenware.

“It’s certainly hollow,” returned Ethel Brown, “but I always supposed tiles were flat things. That’s a tile Mother sets the teapot on to keep the heat from harming the polish of the table.”

They stood about the pile of brown, square-edged pipes, roughly glazed inside and out, through whose length ran three square holes. They asked two workmen as they passed what they were. One said “Hollow tile,” and the other, “Terra-cotta.”

“I suspect they’re both right,” Helen decided. “Probably they’re hollow tile made of terra-cotta.”

“But I thought terra-cotta was lighter brown and smooth. They make little images out of terra-cotta,” insisted Dorothy.

“I’ve seen those,” agreed Margaret, “but I suppose there can be different qualities of terra-cotta just as there are different qualities of china.”

“This stuff is fireproof, any way,” explained Dorothy. “I remember now hearing Mother and the architect talking about it. And they said something about a ‘dead air space.’ That must mean the holes.”

“What’s dead air space for?” inquired Ethel Blue.

“I think it dries up the dampness, or keeps it out so that it doesn’t get into the house.”

“These are useful old blocks, then, even if they aren’t pretty,” decided Helen, patting the ugly pile.

Mr. Anderson strolled toward them again after giving various directions to his men.

“Just how is this tile used?” inquired Dorothy, as he seemed to be more at leisure now.

“We build a wall of this hollow tile,” he answered; “then we put the plaster right on to it. Do you see that the outside is rather rough? That is so the plaster will have something to take hold of. We mix it up of cement and lime and sand and put on three coats. The first one is mixed with hair, and mashed on hard so that it will stick and it is roughened so that the next coat will stick to it.”

“Is the next coat made of the same stuff?”

“Without the hair; and the third coat is as thin as cream and is flowed on to make a smooth-looking outside finish.”

The Walls of Sweetbrier Lodge—Plaster on Hollow Tile

“That’s a lot of work,” commented Dorothy.

“That’s not all we’re going to do to your walls; Mrs. Smith wants them to be a trifle yellowish in tone—a little warmer than the natural color of the plaster—so we’re going to wash on some mineral matter that will give them color and waterproof them at the same time.”

“Killing two birds,” murmured Helen.

“Then the whole house will look plastery except the roof and chimneys,” said Ethel Brown.

“Including the roof and chimneys,” returned Mr. Anderson. “We’re going to use concrete shingles—”

“Concrete shingles! Doesn’t that sound funny!”

“They are colored, so they look like green or red shingles.”

“What color is Mother going to have?”

“Dark green. The chimney is to be made of reinforced concrete.”

“‘Reinforced’ must mean ‘strengthened,’ but how do you strengthen it?” inquired Margaret.

“You’ve seen how we build a mold to pour the concrete in; inside of the mold we build a sort of cage of steel rods. Don’t you see that when the concrete hardens it would be almost impossible for such a reinforced piece of work to break through?”

“Couldn’t an earthquake break it?”

“An earthquake might give a piece of solid concrete such a twist that it would crack through, but suppose the crack found itself up against a steel rod? Don’t you think it would complicate matters?”

The girls thought it would.

“I’m awfully glad our chimney is going to be reinforced,” Dorothy exclaimed, “because up on this knoll we’re going to feel the wind a lot and it would be horrid if the chimney should fall down!”

“It certainly would,” agreed the Ethels, but Mr. Anderson assured them that they need not be afraid of any accident of the sort with a reinforced concrete chimney.

“I’ve seen skyscrapers going up in New York,” said Margaret “and all the beams were of steel. Are you going to use steel beams here?”

“No, we don’t often use steel construction for small houses, but this house is going to be more fireproof than most small houses even if it does have wooden beams. You watch it as it goes on and notice all the points that make for fireproofness. It will interest you,” Mr. Anderson promised as he walked away.

The girls all washed their hands as well as they could with the hose with which the workmen watered the concrete mixture, but they had nothing to dry them on and they walked down the road holding them before them and waving them in the breeze.

“Mother will think we are crazy if she happens to be looking out of the window,” said Dorothy.

“My aunt sent you a message, Dorothy,” said Margaret.

“What aunt? I didn’t know you had an aunt,” replied Dorothy.

“She seems like a new aunt to us; James