"But in time the airships may cause us trouble," continued Ozma, "for if the earth folk learn how to manage them we would be overrun with visitors who would ruin our lovely, secluded fairyland."

"That is true enough," agreed the Wizard.

"Also the desert fails to protect us in other ways," Ozma went on, thoughtfully. "Johnny Dooit once made a sand–boat that sailed across it, and the Nome King made a tunnel under it. So I believe something ought to be done to cut us off from the rest of the world entirely, so that no one in the future will ever be able to intrude upon us."

"How will you do that?" asked the Scarecrow.

"I do not know; but in some way I am sure it can be accomplished. To–morrow I will make a journey to the castle of Glinda the Good, and ask her advice."

"May I go with you?" asked Dorothy, eagerly.

"Of course, my dear Princess; and I also invite any of our friends here who would like to undertake the journey."

They all declared they wished to accompany their girl Ruler, for this was indeed an important mission, since the future of the Land of Oz to a great extent depended upon it. So Ozma gave orders to her servants to prepare for the journey on the morrow.

That day she watched her Magic Picture, and when it showed her that all the Nomes had returned through the tunnel to their underground caverns, Ozma used the Magic Belt to close up the tunnel, so that the earth underneath the desert sands became as solid as it was before the Nomes began to dig.

Early the following morning a gay cavalcade set out to visit the famous Sorceress, Glinda the Good. Ozma and Dorothy rode in a chariot drawn by the Cowardly Lion and the Hungry Tiger, while the Sawhorse drew the red wagon in which rode the rest of the party.

With hearts light and free from care they traveled merrily along through the lovely and fascinating Land of Oz, and in good season reached the stately castle in which resided the Sorceress.

Glinda knew that they were coming.

"I have been reading about you in my Magic Book," she said, as she greeted them in her gracious way.

"What is your Magic Book like?" inquired Aunt Em, curiously.

"It is a record of everything that happens," replied the Sorceress. "As soon as an event takes place, anywhere in the world, it is immediately found printed in my Magic Book. So when I read its pages I am well informed."

"Did it tell you how our enemies drank the Water of 'Blivion?" asked Dorothy.

"Yes, my dear; it told all about it. And also it told me you were all coming to my castle, and why."