COMMENTARY. The two species here noticed are most probably the _Smilax aspera_ and _Convolvulus sepium_. Dioscorides commends the former of these principally as being alexipharmic, and the latter as being soporific. (iv, 142, 143.) Galen and the other Greek authorities, like our author, merely give their general characters. The Arabians would seem to confound it with the other climbing herbs. See Serapion (De Simpl. 41); Avicenna (ii, 2, 724.) Μίσυ, Misy, is one of the escharotic and caustic medicines, with a strong astringency. It is less pungent than chalcitis, owing to the greater tenuity of its parts. And Galen says that chalcitis and sori, in the course of time, change to misy, the change beginning at the surface. * * * * * COMMENTARY. It appears strange that this mineral should now be so little known, seeing it was well known as late as the days of Boerhaave, and is still used medicinally in the East. Boerhaave says of it, “Misy, a yellow mineral very much resembling the marcasite or mundick of our mines, but lighter, and of a less compact nature.... It is a vitriolic mineral, and is reduced by calcination to a colcothar.” (M. M. 184.) Dr. Ainslie, treating of the preparations of copper employed in medicine by the natives of India, says, “Misy is the name of an oxide of copper used by the natives of India against the toothache, and to stain their teeth black.” (Mat. Ind. i, 513.) Dr. Royle, treating of the _misy_ and _sory_ of Dioscorides, states that they had been supposed by Rossius to be sulphurets of copper, “but it is remarkable that _mis_ is a Persian name for copper, and that _missy_ is a name frequently applied in India to sulphate of iron.” (Antiq. of Hindoo Med. 102.) From these descriptions of it we find some difficulty in deciding what mineral substance it was; but see under _Chalcitis_. The following is Dioscorides’s description of the misy: “Of a golden appearance, hard, shining like gold when broken, and glancing like stars.” (v, 116.) He says it has the same powers as _chalcitis_. Galen gives an elaborate description of _misy_ and its cognate fossils _sory_ and _chalcitis_, but says little more than our author respecting its medicinal powers. (De Simpl. viii.) The other Greek authorities supply nothing additional of any great interest under this head. Serapion describes the three substances we have mentioned under the general head “de vitreola,” calling the sory _Zeg rubeum_, the chalcitis _colcothar_, and the misy _Zeg viride_. His account of them is taken entirely from Dioscorides and Galen. (c. 386.) Avicenna confounds them and other metallic preparations under the name of “Atramentum sutorium.” He throws no light on the subject. (ii, 2, 47.) See Rhases (Cont l. ult. 747.) Averrhoes, under the head of _Alceg_, i. e. Vitriolum, gives a translation of Galen’s description already noticed. (Collig. v, 43.) Misy occurs in the works both of Hippocrates and Celsus. The latter uses it as