“The balloon floated just above a ridge that ran along one side of the valley. They could see no one, no ani- mals or sign of any life, but there were trails in the hard sand bed that suggested people occasionally passed this way. Such trails could be misleading, for in the desert they could exist for an eternity, and one could never tell how old they might be.” LostNatureLonelinessDesertSandTrails Book:Empires of Sand by David Ball Source: Empires of Sand by David Ball