THE IMPROVED ART OF FARRIERY. 531 



tion, like that of every preparation of antimony, whose 

 reguline part is not joined with the acid, must be liable 

 to variations, according to the quantity and condition 

 of the acid of the stomach. Farriers frequently give 

 to horses an ounce or two in the day, divided into dif- 

 ferent doses, as an alterative. In the horse, and other 

 quadrupeds of the herbiverous tribe, it acts chiefly as 

 a diaphoretic. The chemists have been accustomed 

 to make the crocus with a less proportion of nitre than 

 what is directed above, and without any farther melt- 

 ing than what ensues from the heat which the matter 

 acquires by deflagration, which, when the quantity is 

 large, is very considerable ; a little common salt is 

 added to promote the fusion. The mixture is put, by 

 degrees, into an iron pot or mortar, somewhat heated, 

 and placed under a chimney ; when the first ladle- 

 ful is in, a piece of lighted charcoal is thrown to it, 

 which sets the matter on fire ; the rest of the mixture 

 is then added by little and little, the deflagration is 

 soon over, and the whole appears in perfect fusion ; 

 when cold, a considerable quantity of scoriae is found 

 on the surface, which scoriae is easily knocked ofl" with 

 a hammer. The crocus prepared in this manner is 

 of a redder colour than that of the former edition of 

 the London Pharmacopoeia. And, indeed, the method 

 now directed by the London College may be considered 

 ^s founded on this. It differs principally from that 

 of the Edinburgh College in the employment of the 

 sea-salt, by which the process is much facilitated. 



