Sugar, mucus, under which term we include the different kinds of gums, and starch, are vegetable oxyds, having hydrogen and charcoal combined, in different proportions, as their radicals or bases, and united with oxygen, so as to bring them to the state of oxyds. From the state of oxyds they are capable of being changed into acids by the addition of a fresh quantity of oxygen; and, according to the degrees of oxygenation, and the proportion of hydrogen and charcoal in their bases, they form the several kinds of vegetable acids. It would be easy to apply the principles of our nomenclature to give names to these vegetable acids and oxyds, by using the names of the two substances which compose their bases: They would thus become hydro-carbonous acids and oxyds: In this method we might indicate which of their elements existed in excess, without circumlocution, after the manner used by Mr Rouelle for naming vegetable extracts: He calls these extracto-resinous when the extractive matter prevails in their composition, and resino-extractive when they contain a larger proportion of resinous matter. Upon that plan, and by varying the terminations according to the formerly established rules of our nomenclature, we have the following denominations: Hydro-carbonous, hydro-carbonic; carbono-hydrous, and carbono-hydric oxyds. And for the acids: Hydro-carbonous, hydro carbonic, oxygenated hydro-carbonic; carbono-hydrous, carbono-hydric, and oxygenated carbono-hydric. It is probable that the above terms would suffice for indicating all the varieties in nature, and that, in proportion as the vegetable acids become well understood, they will naturally arrange themselves under these denominations. But, though we know the elements of which these are composed, we are as yet ignorant of the proportions of these ingredients, and are still far from being able to class them in the above methodical manner; wherefore, we have determined to retain the ancient names provisionally. I am somewhat farther advanced in this inquiry than at the time of publishing our conjunct essay upon chemical nomenclature; yet it would be improper to draw decided consequences from experiments not yet sufficiently precise: Though I acknowledge that this part of chemistry still remains in some degree obscure, I must express my expectations of its being very soon elucidated.