Their fuel is the decaying wood, tree roots and similar material in the soil.
Man, said Ruskin, is an engine whose motive power is the soul; and its fuel is love.
WHEN FUEL AND FOOD ARE PROCURED, the next consideration is, how the latter may be best preserved, with a view to its being suitably dressed.
It is for these reasons that they that are wise are ever careful of both virtue and wealth, for a union of virtue and wealth is the essential requisite of pleasure, as fuel is the essential requisite of fire.
The fuels to be considered are anthracite and bituminous coals, crude petroleum, and coal, generator and water gases.
This and a few matches or a little tobacco on parting, is all he looks for in return for shelter, room for beds on the floor, snow-water laboriously melted, use of the fire, and as much wood as they like to burn, even if it is a barren place, and fuel is the precious far-travelled "drift.
The fuel used is llama dung, costing 80 cents, or 2s.