Narcosis and emulsion reversal by inert gases

Investigations of the effect of high pressures of Na (100 to 130 atmospheres) and of Ar (60 to 80 atmospheres) showed that these gases are effective in reversing the phases of an oil in water emulsion. Nitrous oxide did not cause reversal at pressures as high as 53 atmospheres nor did helium as high as 107 atmospheres. We found CO(2) most effective in reversing the emulsions and attributed this to its chemical properties. It is suggested that these observations may help to explain the narcotic effects of inert gases.