part 18

(1877).—See also C. De Candolle, in _Monogr. Phanerogamar._ i. (1878) 722.

[638] _Medical Facts and Observations_, Lond. vi. (1795) 127.

[639] _Tentamen inaugurale de Swieteniâ Soymidâ_, Edinb. 1794.

[640] Kindly sent us by Mr. Broughton of Ootacamund.

=Chemical Composition=[641]—The bitter principle of the bark has been ascertained by Broughton[642] to be a nearly colourless resinous substance, sparingly soluble in water but more so in alcohol, ether, or benzol. It does not appear to unite with acids or bases, and is less soluble in water containing them than in pure water. It has a very bitter taste, and refuses to crystallize either from benzol or ether. It contains no nitrogen. To this we may add that the bark is rich in tannic acid.

=Uses=—Rohun bark is administered in India as an astringent tonic and antiperiodic, and is reported useful in intermittent fevers and general debility, as well as in the advanced stages of dysentery and in diarrhœa.

RHAMNACEÆ.

FRUCTUS RHAMNI.

_Baccæ Rhamni, Baccæ Spinæ cervinæ; Buckthorn Berries_; F. _Baies de Neprun_; G. _Kreuzdornbeeren_.

=Botanical Origin=—_Rhamnus cathartica_ L., a robust diœcious shrub with spreading branches, the smaller of which often terminate in a stout thorn. It is indigenous to Northern Africa, the greater part of Europe, and stretches eastward to the Caucasus and into Siberia. We have seen stems 50 years old, having a diameter of 8 inches, sent from the government of Cherson, Southern Russia. In England the buckthorn though generally distributed is abundant only in certain districts; in Scotland it occurs wild in but a single locality. Yet in Norway, Sweden, and Finland it grows much further north.

The fruit which ripens in the autumn is collected for use chiefly in the counties of Hertfordshire, Buckinghamshire, Oxfordshire, and also from Wiltshire. The collectors usually prefer to supply the juice as expressed by themselves.

=History=—The Buckthorn was well known to the Anglo-Saxons, and is mentioned as _Hartsthorn_ or _Waythorn_ in their medical writings and glossaries dating before the Norman conquest. The Welsh physicians of Myddfai (“Meddygon Myddvai”) in the 13th century prescribed the juice of the fruit of buckthorn boiled with honey as an aperient drink.

As _Spina Cervina_ the shrub is referred to by Piero de’ Crescenzi of Bologna[643] about A.D. 1305.

[641] The analysis alluded to in the _Pharm. of India_ (p. 444) concerns _Khaya_ (_Swietenia_) _senegalensis_, and not the present species, as my friend Dr. Overbeck has informed me.—F. A. F.

[642] Beddome, _Flora Sylvatica_, Madras,