An apparatus for the determination of differences between the densities of degassed and gas-saturated liquids at atmospheric pressure is described. Differences in density between prepared liquid samples were measured by means of a vibrating-tube densitometer (Anton Paar DMA 602). Density differences at 298.15 K were measured for (liquid-gas) pairs. The liquids included members of the homologous series of n-alkanes (n-hexane, n-heptane, n-octane, n-decane, and n-hexadecane) and l-alkanols (methanol, ethanol, l-propanol, l-butanol, 1-hexanol, l-octanol, and l-decanol). The selected gases were nitrogen, oxygen, argon, carbon dioxide and ordinary air. The density differences for those pairs whose solubility data were available from the literature partial molar volumes of gases in liquids were calculated, and correlated with the internal pressures of liquid solvents.