DISEASES AND TREATMENT OF THE HORSE 113 
day in his feed. Gradually bring him back to his natural feed 
and work again. 
12. Inflammation of the Lungs (Pneumonia). 
This disease is an inflammation of the lung substanct 
itself and is quite commonly met with. The lungs in their 
natural state will float on water. In the first stage of this 
disease the lungs are filled with blood and serum, and they 
are of a dull reddish color; at this stage, if the animal dies, 
the lungs will still float on water. As the disease develops 
the lungs change to a dark, grayish appearance ; if the animal 
dies and the lungs are put in water they will sink. 
Causes. — The causes are much the same as those of con- 
gestion of the lungs and generally afl^ect horses kept m a 
poorly ventilated stable, which has a tendency to weaken the 
lungs. Sudden changes in the weather, such as there" are in 
the fall and spring, are liable to cause this disease. It is also 
sometimes caused by keeping a horse m a warm stable and 
then turning him out in pasture to lie on the cold ground ; 
Fig. 4. — I'osition Assumed During an Attack of Pneumonia. 
by becoming wet and chilled during a cold rain storm ; by 
having a horse clipped and exposed to the cold ; by standing 
in a draft while warm; by inhaling smoke; or by driving 
against a cold wind too soon after having influenza, dis- 
temper, or any of those weakening diseases. It also fre- 
quently follows congestion of the lungs. 
