The room was covered with the things. Rows upon rows of black and white dominos stood upright on end, spaced evenly apart. They were on the floor, the furniture, window ledges, chair rail, every space a domino could be set. They were interspersed with other things Beth couldn't identify, but dominos were prevalent.

She saw this all in a split second, and then wonder took over.

The first domino knocked against the next, sending it into the next and so on. The momentum of falling dominos became a stream, and then a pattern that swirled around and around the floor.

The line climbed up a little ramp to run across the desk and down a set of books piled like stair steps on the other side. Back to the floor to divide into two patterns, each exactly mirroring the other, resembling the carefully trimmed hedges in the garden below.

Next, the dominos ran up to the window ledge and a colorful box there. A domino hit a lever before the next ones ran around the sill, and out popped a jack-in-the-box. Belle laughed and clapped her hands.

The domino stream ran across a ledge and up onto the next windowsill. Again one hit a lever, and out of this box popped a clockwork elephant that lifted its trunk and trumpeted before it sank back into the box.

The adults watched, as entranced as the children, as the line of dominos sped back to the floor. It ran in more patterns, then split again. One domino in the second pattern tripped a switch, shooting a toy train out from the shadows on its track. The train whistled and blew real smoke as it raced around to the end of its run, incidentally knocking down the next domino in the chain.

This stream broke into three, each heading a different direction. One stream zoomed across the floor straight at Jamie before veering aside at the last second. Another whirled into curlicues, like flower petals opening on the floor. The third went up a series of ramps, to clatter across the picture rail under the cornice.

The last domino on the rail fell to land against another on the window seat. This stream ran to another box that sprang open in an explosion of sulfur-smelling smoke.

"That's Danny," Cameron said, sounding as delighted as the children. "He's always loved blowing things up."

Another crack and puff answered the remark as the dominos swarmed down the window seat. The next device they triggered released a string of puppets dancing on a wire, a music box below them playing a merry tune. The dominos ran on, tripping a lever on a clock they ran past. The clock chimed, and from its top issued a line of figures that bowed, danced, or tapped drums in front of them, before they disappeared back into the clock.

"Glockenspiel," Daniel said to Jamie's wide-eyed stare. "Friend and I made it."

The stream now met up with the two others that had been flashing around the room. The dominos ran side by side, three abreast, then knocked into others that grew the stream into four and five, then six and seven across. The dominos parted and flowed into a diamond-patterned design, meeting precisely at the end, the streams dissolving back into three before picking up again for the next diamond.

The diamonds finished, reduced the dominos to two streams again, then one, which zigzagged up ramps to the ceiling fixture, its facets removed. The dominos raced around the rim then fell like a waterfall into a pile below. One knocked into the next row, which tripped another box.

Out popped a clockwork bird, which took wing and flapped around the room. Dominos gathered into a wild swirl, tripping more and more, until they all fell down in the middle of the circle.

A final lever tripped, and a box burst open with a puff of smoke and a ball of glittering paper, which exploded over the room.

Confetti rained down in a gentle shower, the last domino fell, and all was silence.

Mac let out a wild whoop, startling Beth out of her stunned stillness. She had to open and close her mouth a few times, her voice not working, as the others bathed Ian in wild applause.

"Ian, you did all this?" Mac asked.

"Daniel put in the clockworks," Ian said quietly, lifting the first domino to stand it upright again.

"It was all Uncle Ian's idea," Daniel said. "Born in that mathematical brain of his. He came up with the designs and how to make them work. I just put together the clockworks. Uncle Ian's a bloody genius."

Ian said nothing. He showed Jamie how to set up the dominos again. Jamie let him get to five before he knocked them down and shouted happily.

The rest of the family swarmed in, adults and children alike, examining the fallen dominos and Danny's devices, exclaiming in excitement. Hart had pulled off his paper crown, but he bent over the patterns as eagerly.

"You'll have to set them all up again," Hart said. "I want Eleanor to see this."

"Uncle," Daniel said in dismay. "It took us weeks to do this lot."

"Take more weeks," Hart said, without sympathy. "Not Eleanor's fault she's abed. She'll want to see it when she's better."

"True." Daniel brightened, with his usual lightning-swift change of mood. "Auntie El shouldn't miss it. Here, Jamie, help me with these."

He led Jamie to another stream, and Ian rose and came to Beth.

"Daniel's right," Beth said to him. "You are a bloody genius. And here I was afraid . . ."

Ian gave her a puzzled look. "Afraid of what? It was for Jamie. For Christmas."

Beth flung her arms around her husband and pulled his tall body down to her. "Ian, I love you so very much."

Ian's strong arms came around her, his warmth filling his embrace. "I love you, my Beth," he whispered against her hair. "Are you happy?"