sentences:  Bearing such field-hand monikers as "steam flood", "fire flood" and "huff and puff" techniques, these extraction methods - like the Barber Asphalt and Paving Company's 1910 experiment - essentially apply heat to the underground reservoir.This melts the oil - that is, decreases its viscosity - so it can be pumped to the surface.An increasingly successful system now in use is steam assisted gravity drainage (SAGD).