NATURAL HISTORY. 
Besides the human species, other 
animals are subject to this com- 
plaint. It appears in some of the 
finest horses in Poland. In them it 
is situated in the mane, and some- 
times in the long hairs around the 
hoof and fetlock joint. It attacks 
also the different species of the 
canine genus; dogs,. wolves, and 
foxes. Previous to its occurrence 
in the first, the sy mptoms of rabies 
usually appear: the rail is dropped 
between the hind legs, there is a 
flow of frothy saliva from the 
mouth, the sight and appetite are 
impaired or entirely lost ; they are 
snappish, and disposed to bite, 
but their bite does not produce hy- 
drophobia. The .wolf is affected 
in the same manner; he leaves his 
wonted concealments in the woods, 
and runs wildly among the flocks, 
biting, and destroying them, but 
without producing hydrophobia. 
The impossibility of ascertaining 
the true causes of this singular dis- 
ease, has given rise to several vague 
conjectures on the subject; as that 
of Le Fontaine, who attributes it 
to a corruption of the fat. 
It is somewhat remarkable, that 
Plica takes place only among the 
lower class of people; whence some 
lave conceived, that it is to be con- 
sidered merely as a consequence sf 
uncleanliness. 
But, in objection to this opinion, 
it may be urged, that it is un. 
known in the adjoining countries 
subject to the Prussian Govyern- 
ment, where the peasants are ha- 
bituated to the same customs and 
mode of life, or nearly the same, as 
in Poland—that its appearance. 
affords evident relief to the system, 
and its retrocession is produ‘tive of 
dangerous consequences. ‘he idea 
that itis areal and idiopathic disease,. 
[405 
is confirmed also by its occurrence 
in a variety of animals, and by the 
circumstance of its being confined to 
particular parts of the head ; for 
which no reason can be assigned 
on the former supposition, , 
A-peculiarity of climate cannot 
be adduced as a cause-of this disease. 
Poland differs little in this respeét 
from the adjoining countries. ‘The 
summer heat is considerable, the 
thermometer rising frequently to 
98°. 100%. 1049, and the cold in 
winter so great, that it falls some- 
times 10, 15 degrees below o, But 
though the changes in the atmo- 
sphere are so remarkable, at dif. 
ferent periods of the year, they 
take place with the utmost regu- 
larity, the temperature passing, “by 
insensible degrees, from one extreme 
to the other. 
The Poles themselves are a vi. 
gorous, hardy race; inured from 
infancy to labour, and to exposure 
to the vicissitudes of the atmo. 
sphere ; almost regardless of cold, 
they frequently sleep in the open 
air, Their diet consists chiefly of 
animal foad, and they are much 
addi¢ted to the use of spirits. They 
have an equal fondness for other 
strong stimulating liquids. I have 
seen them drink, with the greatest 
pleasure, the salt brine in which 
herrings have been preserved, and 
even nitrous acid diluted with 
water. 
Since no other cause can be 
assigned for this disease, it is pro. 
bable that it. arises, according 
to the general opinion, from con- 
tagion; a contagion which, like 
that of Psora, can betomnianieated 
by contaét only: but this I have 
not been able to ascertain by any 
observations of my own. 
It is said, however, by authors 
Dd 3 of 
