There are two elements which enter into the composition of unguents, the juices and the solid parts. The former generally consist of various kinds of oils, the latter of odoriferous substances. These last are known as hedysmata, while the oils are called stymmata.[694] There is a third element, which occupies a place between the two, but has been much neglected, the colouring matter, namely. To produce a colour, however, cinnabar[695] and alkanet[696] are often employed. If salt[697] is sprinkled in the oil, it will aid it in retaining its properties; but if alkanet has been employed, salt is never used. Resin and gum are added to fix the odour in the solid perfumes; indeed it is apt to die away and disappear with the greatest rapidity if these substances are not employed. The unguent which is the most readily prepared of all, and indeed, in all probability, the very first that was ever made, is that composed of bryon[698] and oil of balanus,[699] substances of which we have made mention already. In later times the Mendesian unguent was invented, a more complicated mixture, as resin and myrrh were added to oil of balanus, and at the present day they even add metopion[700] as well, an Egyptian oil extracted from bitter almonds; to which have been added omphacium,[701] cardamum,[702] sweet rush,[703] honey,[704] wine, myrrh, seed of balsamum,[705] galbanum,[706] and resin of terebinth,[707] as so many ingredients. Among the most common unguents at the present day, and for that reason supposed to be the most ancient, is that composed of oil of myrtle,[708] calamus, cypress,[709] cyprus, mastich,[710] and pomegranate-rind.[711] I am of opinion, however, that the unguents which have been the most universally adopted, are those which are compounded of the rose, a flower that grows everywhere; and hence for a long time the composition of oil of roses was of the most simple nature, though more recently there have been added omphacium, rose blossoms, cinnabar, calamus, honey, sweet-rush, flour of salt or else alkanet,[712] and wine. The same is the case, too, with oil of saffron, to which have been lately added cinnabar, alkanet, and wine; and with oil of sampsuchum,[713] with which omphacium and calamus have been compounded. The best comes from Cyprus and Mitylene, where sampsuchum abounds in large quantities.