The very small lumen of the thick-walled cells contains a dark brown mass which is coloured greenish-black by sulphate of iron; the same coloration takes place throughout the less dense tissue surrounding the the groups of stone-cells, and may in each case be due to tannic matter.
Chemical Composition—Greenheart bark contains an alkaloid which has long been regarded as peculiar, under the name of Bibirine or Bebirine. It was however shown by Walz in 1860 to be apparently identical with Buxine, a substance discovered as early as 1830 in the bark and leaves of the Common Box, Buxus sempervirens L. In 1869 the observation of Walz was to some extent confirmed by one of us,[1987] who further demonstrated that Pelosine, an alkaloid occurring in the stems and roots of Cissampelos Pareira L. and Chondodendron tomentosum Ruiz et Pavon ([p. 28]), is undistinguishable from the alkaloids of greenheart and box.
The alkaloid of bibiru bark, which may be conveniently prepared from the crude sulphate used in medicine under the name of Sulphate of Bibirine, is a colourless amorphous substance, the composition of which is indicated by the formula C₁₈H₂₁NO₃. It is soluble in 5 parts of absolute alcohol, in 13 of ether, and in 1400 (1800, Walz) of boiling water, the solution in each case having a decidedly alkaline reaction on litmus. It dissolves readily in bisulphide of carbon, as well as in dilute acids. The salts hitherto known are uncrystallizable. The solution of a neutral acetate affords an abundant white precipitate on the addition of an alkaline phosphate, nitrate or iodide, of iodohydrargyrate or platino-cyanide of potassium, perchloride of mercury, or of nitric or iodic acid.
Maclagan, one of the earliest investigators of greenheart, has obtained in co-operation with Gamgee[1988] certain alkaloids from the wood of the tree, to one of which these chemists have assigned the formula C₂₀H₂₃NO₄ and the name Nectandria. Two other alkaloids, the characters of which have not yet been fully investigated, are stated to have been obtained from the same source.
Bibiric Acid, which Maclagan obtained from the seeds, is described as a colourless, crystalline, deliquescent substance, fusing at 150° C. and volatile at 200° C., then forming needle-shaped groups.
Commerce—The supplies of greenheart bark are extremely uncertain, and the drug is scarcely to be found in the market. It has been imported in barrels containing 80 to 84 lb. each, or in bags holding ½ to ¾ cwt.
Uses—The bark has been recommended as a bitter tonic and febrifuge, but is hardly ever employed except in the form of what is called Sulphate of Bibirine, which, as we have said, is crude Sulphate of Buxine.[1989] It is a dark amorphous substance which, having while in a syrupy state been spread out on glazed plates, is obtained in thin translucent laminæ. We find it to yield scarcely one-third of its weight of the pure alkaloid.
RADIX SASSAFRAS.
Sassafras Root; F. Bois de Sassafras, Lignum Sassafras; G. Sassafrasholz.
Botanical Origin—Sassafras officinalis Nees (Laurus Sassafras L.), a tree growing in North America, from Canada, southward to Florida and Missouri. In the north it is only a shrub, or a small tree 20 to 30 feet high, but in the Middle and Southern United States, and especially in Virginia and Carolina, it attains a height of 40 to 100 feet. The leaves are of different forms, some being ovate and entire, and others two- or three-lobed, the former, it is said, appearing earlier than the latter.