ON THE VETERINARY MATERIA MEDICA. 47 
here two objects to effect,—the stopping of the purging, and the 
neutralization of the acid which accompanies long-continued pur¬ 
gation; and, therefore, although we were weakening both of our 
medicaments, we hoped that some of their original virtue might 
remain in each to accomplish both our objects. It will, however, 
be for the practitioner to judge, how far a principle of acidity- 
may prevail, requiring the absorbent alone, or mere irritation or 
weakness of the exhalents requiring the catechu, or when it may 
be prudent to mingle the two, although the power of each be 
lessened by the union. 
The catechu must not be given with starch or gruel. Starch 
and gruel are excellent emollients, as well as nutrients, in the di¬ 
arrhoea of the horse, and we should ponder well before we relin¬ 
quish them: but if they fail, and we resort to the catechu, the 
starch must no longer be administered; for a powerless precipi- 
tatejof the tanning matter would be formed by its union with the 
fecula or starch. 
We are not in the habit of giving any of the earths, or earthy 
bases, as they would be incompatible; and so, decidedly, are all 
the metallic salts. Tannate;of copper, or of iron, or of lead, 
would be formed, and the acid with which they were previously 
combined would remain free in the mixture, injurious or destruc¬ 
tive. The student would do well to drop a little of the solution of 
catechu into one of sulphate of copper, or iron, or tartarized anti¬ 
mony, or acetate of lead, and observe the abundant precipitate 
which is given. 
We have used the tincture of catechu with mucli advantage in 
healing recent wounds. Two ounces of the powdered gum were 
digested tea days in a pint of proof spirit. Its astringent property 
rendered it more balsamic than even the complicated and expen¬ 
sive compound, tincture of benzoin. 
ACACIA YERA. —Acacia Gum, or Gum Arabic.— Class 28, Order 1. 
Polygamia , Monacia .—This is the produce of a low, withered- 
looking tree, growing principally in the Barbary states, and 
particularly in Morocco. The gum exudes mostly from the 
weakly trees, and hardens in the air. The white is most esteemed 
for the mixture of paints; the pink is equally good as a demul¬ 
cent : a darker coloured and less soluble variety is imported from 
the East Indies. The gum of the English druggist is adulterated 
with that which is yielded by the cherry and the plum, and a 
variety of other trees. 
