Page 482 - Travels in Arabia (Vol 2)

XXIV.] SOUTHERN ARABIA. 451

cies, but that called moselle, of a dark crimson
colour, is esteemed the best. Soon after the
setting in of the south-west monsoon is con­
sidered to be the period most favourable
for collecting it. Trees growing in the most
elevated positions produce the greatest quan­
tity, which does not agree with the received
opinion of naturalists, viz., that a greater
quantity of gum exudes in a hot than a cold
temperature.
I have been the more minute in my ac­

count of this production, because botanists
appear undecided as to the particular tree
which produces this sanguis draconis in the
East. Two very singular trees, found also
in Socotra, are met with on this coast. Both
grow in very rocky places, and derive nou­
rishment from the soil lodged in cells and
cavities of the limestone hills. The whole
diameter of their trunks consists of a soft

white cellular substance, so easily cut
through that we could divide the largest of
them with a common knife. Camels feed on
the leaves of one, but reject those of the
other. A milk-white juice flows from the
trunk and leaves of both, so acrid, that, if
2 g 2