THREE vacuum distillation apparatuses capable of distilling amounts from 5 gm. to 500 gm. have been constructed for preparative and analytical work particularly in regard to fatty acid esters. They are also efficient for other higher boiling mixtures, such as hydrocarbons, alcohols, amino-acid esters and dicarbonic acid esters. The apparatuses are based, inter alia, on the experience of Dr. Podbielniak in connexion with vacuum fractionation. In the choice of material and construction, particular attention has been given to the question of securing an effective apparatus at a reasonable outlay.