National Geographic : 1930 Oct
THE EXPEDITION IS FERRIED ACROSS THE YALUNG AT MUTIRONG At low water the natives use dugouts to cross the river. At high water this is impossible, owing to theswift, current, and asingle rope bridge is then used. Two dugout canoes are tied together to make them steady. While the supplies were ferried across irithe canoes, the mules and horses had to swim.