In the second book, speaking of the various kinds of disease to which the different periods of life are subject, he writes: “Children are especially subject to serpiginous ulcers of the mouth, called by the Greeks aphthæ.... There are also infirmities due to dentition, such as ulceration of the gums, convulsions, fever, looseness of the bowels; and it is especially the eruption of the canine teeth which produces these disturbances. To these, however, very fat children are more particularly liable, and those, also, who have costive bowels.” In Chapter XXV of the fifth book we find the receipt for a narcotic drug, recommended by the author for producing sleep in persons tormented with odontalgic and other pains. This receipt is very complicated, being composed of ten ingredients, among which are acorns, castoreum, cinnamon, poppy, mandrake, and pepper. Most important for our subject is Chapter IX, of the sixth book, where the author treats of odontalgia. “In toothache, which may be numbered among the worst of tortures, the patient,” says Celsus, “must abstain entirely from wine, and at first, even from food; afterward, he may partake of soft food, but very sparingly, so as not to irritate the teeth by mastication. Meanwhile by means of a sponge he must let the steam of hot water reach the affected part, and apply externally, on the side corresponding with the pain, a cerate of cypress or of iris, upon which he must then place some wool and keep the head well covered up. But when the pain is violent, the use of purgatives is very beneficial, the application of hot cataplasms on the cheek, and the keeping in the mouth of some hot liquid, prepared with fitting medicine, changing this liquid, however, very frequently. For this purpose the root of cinquefoil may be boiled in wine, or that of hyoscyamus (henbane), or a poppy-head, seedless and not too dry, or the root of the mandrake. But in regard to the last three remedies, one must be careful not to swallow the decoction whilst it is kept in the mouth. For the same purpose one may boil the bark of the root of the white poplar in wine, or the scrapings off a stag’s horn in vinegar or figs in mulse[115] or in vinegar and honey. It is useful also to pass repeatedly around the tooth the end of a probe which has first been wrapped around with wool and then dipped in hot oil. It is customary also to apply around the tooth certain remedies, after the manner of plasters. For this purpose the inside of the peel of dried, bitter pomegranates may be pounded with equal quantities of gall-nut and pine bark; to these must be added a little minium[116] and the whole mixed together with the addition of rain water to form a paste; or else a similar paste may be formed with equal parts of panax,[117] poppy, peucedanum,[118] and taminia grape[119] without stones; or with three parts of galbanum to one of poppy. On the cheek, however, must be applied at the same time the cerate spoken of above, covered over with