"That's right," Uncle Henry replied. "Let's get some scissors and we'll use our big sheet of cardboard to make a cap for Paul's head that will show you just how the slant of the earth's axis makes it hotter in summer and colder in winter." "Ooh!" exclaimed Paul, "I always thought it was hot in summer because the earth got nearer to the sun then." "Lots of people think that, too," said Uncle Henry, "but it isn't so. The earth is really farther from the sun in summer." Betty ran for the scissors, and Uncle Henry cut out a big circle from the stiff cardboard. Then he cut out an opening in the centre of it that fitted Paul's head just as a stiff straw hat would that was a size too big for him. The circle of cardboard dropped down until it rested on Paul's ears and on the bridge of his nose. This cardboard brim represented the "plane of the earth's equator," just as the pane of glass represented the "plane of the ecliptic." Since the "plane of the equator" is always at right angles to the slanting axis of the earth, the "plane of the equator" is always at a slant to the "plane of the ecliptic." If you will run a long hat-pin through an orange, and sink the orange exactly to its middle in a glass bowl filled with water, holding the hat-pin at a slant, you will see that the equator of the orange is at a slant with the surface of the water. Half of the orange's equator curves up above the water, while half of it curves down under the water's surface. If you fasten a cardboard ring around the orange at the equator the cardboard will then be at an angle with the surface of the water, which represents the "plane of the ecliptic." Uncle Henry cut two long strips from what was left of the cardboard and crossed the strips over the top of Paul's head, fastening the four ends of them to the round cardboard brim close to his head. [Illustration] After this Uncle Henry rolled a sheet of the scratch paper round a pencil, put rubber bands tightly around it, cut the end to bend up and make a foot and pinned the foot to the cardboard strips at the place where they crossed. When Paul had it all on he looked very funny with the pencil sticking straight up from the top of his head, and his eyes just peeping over the cardboard brim on each side of the strip down the middle of his nose. "Now come on, Mr. Earth," said Uncle Henry, "It's time for you to spin round the lamp-sun for another year or two." So Paul held his head on a slant and kept it so that the pencil always pointed in the same direction as he went round the lamp. These four little pictures show how he looked at the four sides of the sun where the earth is in Winter, Spring, Summer, and Autumn. [Illustration]