COMMENTARY. The wild rue is the _Peganum Harmala_, L. The other species is the _Ruta graveolens_. According to Florentinus, it kills the fœtus in utero (Geopon. xii, 25.) Dioscorides’s two chapters on the Peganum are so long that we can scarcely attempt an abstract of them. Both species, he says, are caustic, calefacient, ulcerative, diuretic, emmenagogue, astringent, and alexipharmical. (iii, 45, 46.) It occurs in the Hippocratic treatises, and in the works of Celsus. Our author abridges the interesting account of it given by Galen. The Arabians treat of the two species very elaborately, but in the main follow Dioscorides. See Avicenna (ii, 2, 571); Serapion (c. 300); Averrhoes (Collig. v, 42.) We may just mention that the _Ruta graveolens_ still retains its place in our Mat. Med., and that the seeds of the other, _Peganum Harmala_, are still kept in the shops. See Gray (Suppl. to Pharmacop. 116.) The Turks use its seeds as a spice, in like manner as they were used in the time of Pliny. (H. N. xx, 51.) Πίσσα, Pix, _Pitch_; dry pitch is desiccative in the second degree, but less calefacient, while the liquid is contrariwise. They have some detergent and digestive powers, and also discutient and acrid. They therefore remove leprous nails, cleanse lichen, and digest swellings. But the liquid is more powerful, so as to be serviceable in a linctus for asthma and empyema. The dry is more agglutinative of wounds. * * * * * COMMENTARY. Pliny says of pitch, “Phthisicis etiam cyathi mensura quidam dederunt, et contra veterem tussim.” (H. N. xxiv, 24.) Averrhoes also recommends it in such cases. (Collig. ii, 42.) See, however, more fully on the virtues of pitch, Dioscorides (i, 94), who recommends the liquid pitch in phthisis, empyema, coughs, asthma, and cases of difficult expectoration; also as an external application to leprous nails, hard tumours of the uterus, fissures of hands and feet, &c. The liquid pitch of the ancients was evidently tar; the dry was the same boiled until it became hard. The latter is often called παλιμπίσσα. See Dioscorides (i, 94, 97) and Pliny (xxiii, 1.) Πισσέλαιον, Oleum picatum, _Pitched Oil_, is formed from liquid pitch consisting of a more attenuate substance than it. * * * * * COMMENTARY. According to Sprengel, the π. of Dioscorides is the same as _Tar-water_, so celebrated as the grand panacea by Dr. Berkley in his ingenious work called ‘Siris.’ It is called ὀροπίσση by our author in another place. (iii, 74.) The _Pissasphaltum_ of the ancients, according to Dr. Hill, was the _Pix Mineralis_, or Earth Pitch of the moderns. Πιστάκια, Pistachia, _Pistachio Tree_; its fruit when eaten is moderately stomachic, and removes obstructions of the liver, and more especially a decoction of the light and aromatic parts of it in wine. It also relieves those who have been bitten by reptiles. * * * * *