The effect of dissolved gas on the hydrophobic attraction between double-chained surfactant monolayers physisorbed on mica has been studied using a surface forces apparatus (SFA). Distance vs time data were obtained over the full distance regime from D approximate to 1000 Angstrom down to contact using the dynamic SFA method. Removal of dissolved gas was seen to reduce the range of the attraction while the short-range attraction (under similar to250 Angstrom) remained unchanged. The implications for the possibility of two distinct force regimes in the interactions between hydrophobic surfaces are discussed.