98 THE GEOGRAPHY OF PLANTS. 



the country of gums and balsams, a large num- 

 ber of its plants and trees abounding in sucn 

 exudations. Gum arabic is obtained in large 

 quantities from Acacia vera and A. ardbica. 

 The best and whitest comes from the last- 

 named species. It is gathered in vast quanti- 

 ties from the trees growing in Arabia Petrsea, 

 near the foot of Mount Sinai ; and is so nutri- 

 tious, that the Moors who collect it live almost 

 entirely upon it during the whole of the gum 

 harvest, which lasts five weeks, and the subse- 

 quent journey of transport. Gum Senegal, an 

 inferior kind of gum arabic, is the produce of 

 Acacia Senegal, a tree which inhabits Arabia 

 and the interior of Africa, and sometimes forms 

 large forests. In 1839, 15,628 cwt. of gum 

 arabic, and 24,698 cwt. of gum Senegal, were 

 imported into this country. Several other 

 species of mimosa and acacia also inhabit Arabia. 

 The balm of Mecca is the produce of a tree 

 growing between Mecca and Medina, (Balsamo- 

 dendron opolalsamum,) and the balm of Gilead 

 of another species of the same genus, (B. 

 Gileadense,) also a native of Arabia. The balm 

 of Gilead was held in very high estimation in 

 the most ancient times, as a medicine and cos- 

 metic. The Ishmaelites carrying Arabian 

 commodities into Egypt, made it part of their 

 merchandise, (Gen. xxxvii. 25 ;) and it was 

 among the presents which Jacob sent to 

 Joseph while ruler of Egypt, (Gen. xliii. 

 11.) The value which was set upon it as 

 a healing medicine of extraordinary virtue, 



