and tomatoes are made from the soil, the air, the water and the sunshine."

"Are there tomatoes in the air?" asked Mab.

"Well, if it were not for the things in the air, the oxygen, the nitrogen
and other gases, about which you are too young to understand now, we could
not live grow, and neither could plants. Plants also have to have water to
drink, as we do, and food to eat, only they eat the things found in the
dirt, and we can not do that. At least not until they are changed into
fruits, grain or vegetables."

Hal and Mab never tired looking at the tomato plants growing in the box in
the house. Each day the tiny green leaves became larger and raised
themselves higher and higher from the earth.

"Soon they will be large enough to transplant, or set out in the garden,"
said Daddy Blake.

Two or three days after their father had told Hal and Mab why seeds grow,
the children, coming home from school, saw something strange in their
garden.

There was a man, with a team of horses and the brown earth was being torn
up by a big shiny thing which the horses were pulling as the man drove
them.

"Oh, what's that in our garden?" cried Hal to Uncle Pennywait.

"It's a man plowing," said Hal's Uncle.