302 Veterinary Medicine. 



against the soft palate and the delay of deglutition even for an 

 instant, it also assures a continuous flow of liquid into the phar- 

 ynx, and some of this must pass into the larynx during inspir- 

 ation. 



Bouley adds the action of astringent draughts in constricting 

 the fauces and pharynx and favoring the passage of food into 

 the larynx. However this may be there can be no doubt that, 

 as in the horse, contact of the pharyngeal mucosa and that of 

 the margin of the larynx with local anaesthetics (ether, chloro- 

 form, chloral, carbolic acid, cocaine, etc.), lessens the alert con- 

 trol over the muscles and favors inhalation. 



Oiled boluses which are said to slide more readily into the larynx 

 (Albrecht), and the finely divided particles in gruels (Mazoux), 

 and the acid element in cider (Cagny), are variously incrimi- 

 nated. Oils and melted lard, while less irritating to larynx and 

 bronchia, are specially injurious in excluding oxygen and pre- 

 venting aeration of the blood, and elimination of carbon dioxide. 



Inflammation of the pharynx and larynx — catarrhal, phleg- 

 monous, or croupous — -disturbs the sensibility and muscular 

 control, and makes the giving of drenches much more dangerous, 

 and the same has been noticed in pharyngeal tuberculosis and 

 tetanus. 



Tympany of the rumen is a great source of danger. The 

 hurried breathing caused by the compression of the lungs by the 

 diaphragm favors inhalation. The closure of the demicanal by 

 the stretching of its pillars which spread out on the walls of the 

 distended rumen, hindering alike the exit of gas from the viscus 

 and the entrance of liquids descending the oesophagus, favors 

 the return of the liquid to the pharynx by regurgitation, and its 

 entrance into the larynx. Finally the compression of the oeso- 

 phagus between the two pillars of the diaphragm, stretched by 

 the forward pressure of the distended rumen, acts in the same 

 way. 



Milk-fever in cows (parturient paresis) has been in the past a 

 common cause of inhalation pneumonia. In the general paraly- 

 sis of the fully developed disease the pharynx participates, and 

 when treated by drenches given by the mouth the descent of the 

 medicament into the lung was a frequent occurrence. If the 

 patient survived the coma, she had to face an attack of broncho- 



