Glinda the Sorceress had asked Cap'n Bill to remain in the Emerald
City and take charge of the royal palace while everyone else was away,
and the one-legged sailor had agreed to do so.

They loaded the back end of the Red Wagon with everything they thought
they might need, and then they formed a procession and marched from
the palace through the Emerald City to the great gates of the wall
that surrounded this beautiful capital of the Land of Oz. Crowds of
citizens lined the streets to see them pass and to cheer them and wish
them success, for all were grieved over Ozma's loss and anxious that
she be found again. First came the Cowardly Lion, then the Patchwork
Girl riding upon the Woozy, then Betsy Bobbin on her mule Hank, and
finally the Sawhorse drawing the Red Wagon, in which were seated the
Wizard and Dorothy and Button-Bright and Trot. No one was obliged to
drive the Sawhorse, so there were no reins to his harness; one had
only to tell him which way to go, fast or slow, and he understood
perfectly.

It was about this time that a shaggy little black dog who had been
lying asleep in Dorothy's room in the palace woke up and discovered he
was lonesome. Everything seemed very still throughout the great building,
and Toto--that was the little dog's name--missed the customary chatter
of the three girls. He never paid much attention to what was going
on around him, and although he could speak, he seldom said anything,
so the little dog did not know about Ozma's loss or that everyone
had gone in search of her. But he liked to be with people, and especially
with his own mistress, Dorothy, and having yawned and stretched
himself and found the door of the room ajar, he trotted out into the
corridor and went down the stately marble stairs to the hall of the
palace, where he met Jellia Jamb.