If you missed it, here's chapter 4.
The short drop drove Rowan’s ribs into the mole’s shoulder and spattered his face with something cold and wet. The grainy taste of earth met his tongue as he swept it around his lips.
His mole lurched sideways, and then struggled upwards and level again. Mud slurped like the last drops of a milkshake being sucked through a straw, obviously hindering the mole’s progress.
Once again Rowan was engulfed in darkness. If he stayed in the Pockets much longer, he’d have to learn to see in the dark. The sound of other moles squelching through the mud came from ahead, and soon his own carrier was lumbering after them.