Excess molar volumes V-E at 298.15 K and atmospheric pressure for 1-propanol and 1-hexanol + butyl methyl ether, + dipropyl ether or + dibutyl ether have been calculated from densities measured with a vibrating-tube densimeter. The V-E are negative over the whole mole-fraction range and nearly symmetrical for all the systems investigated. For each monoether, the V-E decreases as the chain length of the 1-alcohol increases. For each 1-alcohol, the V-E increases as the chain length of the symmetrical di-n-alkyl ethers increases. Moreover, for the butyl methyl ether (an asymmetrical monoether), the V-E is more positive than of the immediately higher symmetrical dipropyl ether. These results, together with previously published excess molar enthalpies H-E, suggest the formation of hydrogen bonds between the functional group (-OH) of the 1-alcohol and the (-O-) atoms of the monoethers.