There were only two which seemed to be available; one of these was the bed, and the other the chimney.

If any search was made, of course the soldiers would explore the bed first; and the chimney seemed the most practicable.
There was no time for consideration, for the woman had already opened the door, and was answering the questions of the Confederate officer; so Tom sprang into the fireplace, and, by the aid of the projecting stones, climbed up to a secure position.

The chimney was large enough to accommodate half a dozen boys of Tom's size.

The fire had gone out, and though the stones were rather warm in the fireplace, he was not uncomfortable.
The fears of the lady of the house proved to be well grounded this time, for the party had actually come in search of her "old man;" and what was more, the officer announced his intention not to leave without him.
"He's gone away fur a week, and he won't be hum before the fust of August, no how," said the woman resolutely, and adopting Tom's suggestion to the letter.
"All nonsense, woman! He is about here, somewhere, and we will find him." "You may, if you kin." The officer then went out at the back door, as Tom judged by his footsteps, and the woman asked one of the children what had become of the other soldier man.

The boy said he was up chimney.