VETERINARY MATERIA MEDICA. 
465 
Water impregnated with iron is often employed as a drink. 
Stimulants, diuretics, and vegetable tonics, are often associated 
with the preparations of iron, varying according to the excitation 
or the effect, more or less complicated, that is wished to be pro¬ 
duced. In every case, to obtain success from the exhibition of iron, 
it must be employed for a long time. 
Peruvian Bark, in all its varieties, may be placed at the 
head of the vegetable tonics. It has little action, either applied to 
the skin in a state of powder, or in an aqueous vehicle; but when 
it is brought into contact with a mucous membrane, or a part de¬ 
prived of the cuticle, it has a marked astringent effect. 
When administered internally, in tolerably strong doses, it pro¬ 
duces excitement and heat in the gastro-intestinal canal, a slight 
increase of pulse, and increased activity of the greater part of the 
functions : but its powers of excitement are not the least remark¬ 
able or important which it possesses. This valuable drug pos¬ 
sesses the property of impressing on the tissues certain modifica¬ 
tions unknown in their nature, but perfectly known in their re¬ 
sult ; and tending more effectually than any other bitter tonic, 
or than any thing with which it can be compared, to prevent 
both the attack and the exacerbation of certain diseases. 
The salutary influence of this drug is equally remarkable, but 
also in a way scarcely more understood, in arresting those affec¬ 
tions which are characterised by a tendency, altogether peculiar, 
to decompose the blood and disorganize the tissues. Hence it 
used to be called an antiseptic or antiputrescent . 
Whatever be its mode of action, experience has shew r n that the 
bark is highly useful in the contagious typhus, and malignant 
epidemic of cattle; in gangrenous affections of the lungs; in 
certain varieties of acute mange; in that disease generally, and 
in all inflammations that threaten to terminate in gangrene. 
The immoderate or improper use of bark, as that of all medi¬ 
cines endowed with great pow r er, may be injurious. Acute irri¬ 
tation of the digestive organs w r ould more especially counter-indi- 
cate its employment. 
The salts of the cinchona have not. superseded the use of 
the bark itself; for although the other substances with which 
it is naturally associated have but a secondary medicinal ac¬ 
tion, they may, and do in many cases, advantageously mo¬ 
dify the agency of the main principle. We have, however, used 
the sulphate of quinine with considerable benefit in the chorea 
of the dog, and especially when it was characterised by periodi¬ 
cal exacerbation. 
A veterinary surgeon, under the impression that the rot of* 
sheep bears some analogy to the pernicious intermittent fevers of 
the human being, has strongly recommended the use of the bark. 
