part 33

(1878).

[1230] Fraser, _Journey into Khorasān_, 1825. 118; Polak, _Persien, das Land und seine Leute_, ii. (1865) 282.

Of the three or four other species of _Dorema_, _D. Aucheri_ Boiss.[1231] affords very good ammoniacum, as we know by an ample specimen of the gum deposited together with the plant in the British Museum by Mr. W. K. Loftus, who in 1751 collected both at Kirrind in Western Persia, where the plant is called in Kurdish _Zuh_. Boissier[1232] includes as _D. Aucheri_ another plant, called by Loftus _D. robustum_, the gum of which is certainly different from ammoniacum. Of the plant itself there are only _fruits_ in the British Museum.

=History=—The first writer to mention ammoniacum is Dioscorides, who states it to be the juice of a _Narthex_ growing about Cyrene in Libya, and that it is produced in the neighbourhood of the temple of Ammon. He says it is of two sorts, the one like frankincense in pure, solid tears, the other massive, and contaminated with earthy impurities. Pliny gives essentially the same account.

The succeeding Greek and Latin authors on medicine throw but little light on the drug, which however is mentioned by most of them as used in fumigation. Hence we find such terms as _Ammoniacum thymiama_,[1233] _Ammoniacum suffimen_, _Thus Libycum_.

The African origin assigned to the drug by Dioscorides, has long perplexed pharmacologists; but it is now well ascertained that in Morocco a large species of _Ferula_ yields a gum-resin having some resemblance to ammoniacum, and still an object of traffic with Egypt and Arabia, where it is employed, like the ancient drug, _in fumigations_. There can be but little doubt we think, that the ammoniacum of Morocco is identical with the ammoniacum of the ancients; it may well have been imported by way of Cyrene from regions lying further westward.[1234]

Persian ammoniacum or the ammoniacum of European commerce may also have been known in very remote times, though we are unable to trace it back earlier than the 10th century, at which period it is mentioned by Isaac Judæus[1235] and by the Persian physician Alhervi.[1236] Both these writers designate it _Ushak_, a name which it bears in Persia to the present day.

=Collection=—The stem of the plant abounds in a milky juice which flows out on the slightest puncture. The agent which occasions the exudation is a beetle, multitudes of which pierce the stem. The gum, the drops of which speedily harden, partly remains adherent to the stem and

## partly falls to the ground; it is gathered about the end of July by

the peasants, who sell it to dealers for conveyance to Ispahan or the coast.[1237]

[1231] Fig. in Bentley and Trimen,