the tooth, at other times in the nerve, and at others in the gums. The dental substance may become painful, owing to bad “complexion” (viz., constitution), without there being any morbid matter in it. When, however, such matter exists, it may proceed from the head or from the stomach, and in certain cases it gives rise to an apostema of the tooth; in other cases it corrodes the latter; and at other times generates (!) in it a worm, which in its turn corrodes the tooth. In regard to the diagnosis of dental pains, it is necessary first of all to examine the state of the gums, that is to say, to observe whether these, in the aching spot, appear healthy, or whether, on the contrary, they are discolored or tumid, sanguinolent, suppurating, or the seat of corrosion or putrefaction, or if, when pressure is put upon them, an exit of matter is produced. In such cases it may be considered that the gums are the seat of the pain. But if none of these symptoms are observed, and if, on comparing the gums of the aching spot with the other gingival regions, no difference is observed, this means that the cause of the pain exists either in the substance of the tooth itself, or else in its nerve. In this latter case the pain is usually very violent, and principally localized in the root of the tooth, but also extending along the jaw, and the tooth itself is often, as it were, benumbed. When, however, the pain is not situated either in the gums or in the dental nerve, but in the very substance of the tooth, this latter is very often corroded (carious), and very often in the hollow there exists a worm; and this may be deduced from the fact that during the intervals of calm the patient sometimes feels a peculiar sensation, the movement of the worm in the diseased tooth; when, however, these signs are wanting, we shall find at any rate that the whole tooth is painful in the direction of its length, instead of the pain being localized in the root of the tooth and radiating along the jaw. When the cause of the pain resides in the gums the extraction of the tooth is neither necessary nor beneficial, but is, on the contrary, always harmful, since, in spite of the loss of the tooth, the cessation of the pain is not obtained; when the pain is situated in the tooth itself, the removal of the latter always makes the pain cease; lastly, when the dental nerve is the seat of the evil, the removal of the tooth sometimes takes away the pain, at other times it does not. Among the many anti-odontalgic remedies, Arculanus enumerates pepper mixed with tar, pepper with asafetida, mustard seeds with asafetida, and the like. When a tooth is to be cauterized, it is necessary to protect the healthy teeth with bits of cloth dipped in rose water or else with some kind of paste. Sometimes it is useful to drill the tooth with a small trephine so that the cautery may act more deeply, thus giving better results.