In the course of the investigation of copals derived from leguminous plants1) their volatile oils were also prepared. However, the information concerning them is very meagre. As to their composition not the least is known and in most instances not even their physical constants have been ascertained.
Zanzibar copal from Trachylobium verrucosum (Gartn.), Oliv. The volatile oil2) boils in the main between 200 and 215°, apparently with decomposition.
Sierra Leone copal3), probably from Copaifera Guibourtiana, Benth. (Guibourtia copallifera, Benn.). The oil4) distils largely between 147 and 160°.
Loango copal. Under diminished pressure (? mm.) the oil5) distills principally at 160°.
Benin copal yields 2,7 p.c. of volatile oil6) that distils between 180 and 256°.
1) Comp. also the oils derived from coniferous copals, p. 9.
2) Stephan, Arch, der Pharm. 234 (18%), 560.
3) According to Tschirch (Die Harze und die Harzbehalter, Leipzig 1906, II. Ed. Vol. II, p. 755) the West African copals or copaiba-copals are derived from Caesalpinioidae, many also from Copaifera species.
4) M. Willner, Arch, der Pharm. 248 (1910), 285.
5) Ibidem 273.
6) M. Kahan, ibidem 439.
Kameroon copal from Copaifera Demeusii, Harms1). A light yellow oil-); b. p. 145 to 155°; d 0,830.
Angola copal contains 2 p.c. of volatile oil2); b.p. 140 to 160°; d 0,853.
Brazil copal8), principally from Hymenaea Courbaril, L. and other species of H. Volatile oil 2,66 p.c; b. p. 245 to 255° 4).
Columbia copal. Derived from the same species as the previous one. Oil yield 6,6 p.c; b. p. 210 to 220° in vacuum (? mm.)4).