`` stop that ' '' tavi shouted he threw another biscuit , to no effect a thick strand of the braided rope parted with a whining snap , and tavi 's heart lurched as the rope spun and swung from side to side he glanced below him another twenty feet to ground he 'd never be able to fall that far without hurting himself , possibly too badly to continue another strand parted , and tavi swayed wildly back and forth , his heart hammering high in his throat arms and legs shaking with excitement , tavi took one last glance down ( fifteen feet , or a little more ? )