TOXICOLOGY. 357 



copious discharge of saliva ; the mucous membrane of the 

 conjunctiva is injected ; the animal is dejected, and some- 

 times the tongue is protruded. 



The limbs are often drawn under the body ; the head is 

 depressed ; the back is arched, and the coat may be rough 

 and staring. 



In some instances the animal speedily becomes comatose, 

 while in other cases he is very violent, dashing his head 

 about wildly. 



Spasmodic contractions and twitchings of the muscles are 

 often developed. 



The breathing is quickened and difficult, and the tem- 

 perature is usually somewhat elevated. The pulse is 

 sometimes accelerated, and the artery hard and the volume 

 diminished, while in other instances the frequency is not 

 increased and the volume is fuller. 



The bowels are usually constipated, but there may be 

 diarrhoea and fostid stools. 



Pain is often, but by no means always, manifested. 



In Wales, roaring is said to be the first symptom of lead 

 poisoning in the horse. 



CHRONIC LEAD POISONING — The symptoms of 

 chronic lead poisoning are produced by the ingestion of 

 lead in small quantities over an extended period of 

 time. 



This form of poisoning is chiefly met with in the neigh- 

 bourhood of smelting works, where particles of lead or its 

 salts are disseminated over the grazing pastures, and also 

 probably where lead enters the system through contaminated 

 water-supply. 



We are not aware whether any cases proceeding from the 

 latter cause have been described, but some time ago a 

 suspicious case came before our notice. 



The appetite is impaired, and the coat becomes unhealthy, 



