BOTANIC MATERIA MEDICA, 329 
and containing from 3 to 6 seeds. Acacia ex- 
udes spontaneously from the trees or from in- 
cisions made into the bark of the tree, and oc- 
curs in commerce in the form of spheroidal 
tears, or in broken, angular fragments with 
shining and glass-like surfaces, showing many 
minute cracks or fissures. The best qualities 
of gum are opaque, from the numerous fis- 
sures, and nearly colorless; inodorous, with an 
insipid and mucilaginous taste. Gum Arabic 
is insoluble in alcohol, but soluble in water, 
The aqueous solution gives no precipitate with 
neutral acetate of lead, but forms with the sub- 
acetate an opaque, white precipitate, and is not 
colored blue by idodine. Gum Acacia contains 
arabin, or arabic acid, in combination with the 
salts of dime, magnesium and potassium, The 
varieties of Acacia are numerous, and are pro- 
duced from the species found in Morocco, Cape 
Colony and Australia. The Kordofan gum, 
just described, is the most valuable; the next 
in value is the Senaar gum. The Acacia 
known as the Savakin (Suakin) gum is very 
brittle and of handsome appearance, but is not 
so freely soluble in water as the above varie- 
ties. 
The gum known as the East India is mostly 
obtained from Eastern Africa, and shipped from 
the port of Bombay. The Senegal gum is usu- 
ally found in larger tears than the preceding, 
more transparent, and of yellow or brouwn-red 
color. The North American gum (Mezquite), 
from the tree (described by Messrs. Torrey and 
Gray) Algarobia Glandulosa, found in western 
Texas and Mexico is mostly of a red-brown or 
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