POISONS, POISONOUS SNAKES AND INSECTS, ETC. 389 



ternally in veterinary practice, except in cases of farcy, dis- 

 temper, and glanders, where we prescribe it on the principle 

 of employing one poison to neutralize and destroy another 

 lurking in the blood. 



Tar. — This substance is not a poison ; but it is not best to 

 give it to the horse unless well mixed with grease, as, in its 

 fresh state, it is apt to choke the animal, and has been known 

 to form balls in the stomach that killed him. It has some 

 valuable pectoral properties, when mixed with other ingredi- 

 ents. The oil of tar should not be used. 



Turpentine. — Turpentine is an excellent constituent of ex- 

 ternal applications, such as liniments, the best of which can 

 hardly be made without using it to some extent. It is a 

 rubefacient, (as those substances are called which produce 

 redness of the skin,) and, opening the pores, it prepares the 

 way for the other ingredients of the liniment to act ; but, 

 given internally to the horse, it is poisonous to both the di- 

 gestive and urinary organs. The oil of turpentine should 

 not be used at all. The turpentine from the tree is better 

 than either. 



Tartar EmUic. — This may be used advantageously, in small 

 doses, to abate fevers, and is particularly valuable in inflam- 

 mation of the lungs and all catarrhal affections. It is b, 

 powerful nauseant, and, in large quantities, has the effect of 

 an active poison. In doses of from a drachm to a drachm 

 and a half, when given in connection with niter and digitalis, 

 it excites the secretions of the skin, acting as a powerful 

 diaphoretic as well as diuretic. In overdoses it is apt to do 

 injury. As the horse can not vomit, it is safest to accom- 

 pany tartar emetic with a small dose of salts. 



Groton Oil. — Great danger attends the use of croton oil in 

 veterinary practice. It is admissable only in very extreme 

 cases of costiveness and stricture. Such is the rapidity and 



