such cases it is caused by a reflex nervous irritation.
The proper treatment in all cases of chronic cough is to ascertain the
nature of the disease of which it is a symptom, and then cure the
disease if possible and the cough will cease.

The treatment of the affections will be found under their appropriate
heads, to which the reader is referred.

PLEURODYNIA.

This is a form of rheumatism that affects the intercostal muscles; that
is, the muscles between the ribs. The apparent symptoms are very similar
to those of pleurisy. The animal is stiff and not inclined to turn
round; the ribs are kept in a fixed state as much as possible. If the
head is pulled round suddenly, or the affected side struck with the
hand, or if the spaces between the ribs are pressed with the fingers,
the animal will flinch and perhaps emit a grunt or groan expressive of
much pain. It is distinguished from pleurisy by the absence of fever,
cough, the friction sound, the effusion into the chest, and by the
existence of rheumatism in other parts. The treatment for this affection
is the same as for rheumatism affecting other parts.

WOUNDS PENETRATING THE WALLS OF THE CHEST.

A wound penetrating the wall of the chest admits air into the thoracic
cavity outside the lung. This condition is known as pneumothorax and may
result in collapse of the lung. The wound may be so made that when the
walls of the chest are dilating a little air is sucked in, but during
the contraction of the wall the contained air presses against the torn
part in such manner as entirely to close the wound; thus a small
quantity of air gains access with each inspiration, while none is
allowed to escape until the lung is pressed into a very small compass
and forced into the anterior part of the chest. The same thing may occur
from a broken rib inflicting a wound in the lung. In this form the air
gains access from the lung, and there may not be even an opening in the
walls of the chest. In such cases the air may be absorbed, when a
spontaneous cure is the result, but when the symptoms are urgent it is
recommended that the air be removed by a trocar and cannula or by an
aspirator.

It is evident that the treatment of wounds that penetrate the thoracic
cavity should be prompt. It should be quickly ascertained whether or not
a foreign body remains in the wound; then it should be thoroughly
cleaned with a solution of carbolic acid, 1 part in 40 parts of water.
The wound shoul