DISEASES AND TREATMENT OF THE HORSE 831 
mostly affects the capillary blood vessels of the skin, but in 
some cases affects the lining of the lungs and air passages. 
Causes. — It is generally an after effect of some other 
disease, such as influenza, distemper or some other weaken- 
ing ailment. Horses that are overworked, thin and run down 
in condition are more liable to be attacked by it, especially if 
neglected, turned out at night or allowed to remain exposed 
to unfavorable weather conditions. A chill as a result of 
such exposure is a good ioundation for button farcy. It 
makes its appearance more frequently in the spring and fall. 
Symptoms. — The blood is very thin, almost like water. 
Direct symptoms often appear very suddenly. A horse may 
be apparently in his usual health when left for the night, but 
Fig. 26. — Button Farcy (Purpura Hemorrhagica). 
found in the morning literally covered with patches of swell- 
ing. Some parts of the skin may be affected more than 
others. We have attended cases where the eyelids were so 
swollen that to see was impossible, where the lips were 
swollen to such an extent that it was impossible to eat, and 
where the swelling extended to the sheath and legs. Small 
spots appear all over the skin, especially upon the sides "of 
