Nearly thirty years ago Dobereiner observed, when preparing formic acid by distilling a mixture of starch, peroxide of manganese and sulphuric acid, that the liquid which passed into the receiver contained a small quantity of oil which rendered it turbid. To this oil Dobereiner gave the fanciful name of “ artificial oil of ants,” though the very limited quantity in which he was able to procure it prevented him from determining almost any of its properties. The author’s attention was first directed to the subject in 1840, when he found that the oxide of manganese was unnecessary, and that the oil could be readily prepared by operating on most vegetable substances with either sulphuric or muriatic acid. The oil, on analysis, was found to have the formula C 15 H 6 O 6 , and to contain oxygen and hydrogen in the proportions to form water, while all other oils and fats contain an excess of hydrogen.