492 MATERIA MEDICA 



from the smell of meat, smoke, or f\it. For some purposes, or 

 where it is inconvenient to boil the gruel, a little oat, barley, or 

 wheat meal may be stirred into warm or cold water. 



It is a good practice to accustom horses to drink gruel, as, 

 after a hard day, many hunters show a disinclination to eat, but 

 will drink with avidity ; and if they will drink gruel instead of 

 water, it is not of much consequence if they fast for some time. 

 No horse, it should, however, be remembered, is fit for hard 

 Avork if he be not a good feeder ; but the best horse may refuse 

 his food if forced to over-exertion. 



GUAIAC. — Guaiacum officinale. This tree is a native of 

 Jamaica, Hispaniola, and some parts of America. Every part 

 of it possesses medicinal properties, but the wood and gum alone 

 are used. The former is sometimes employed in human me- 

 dicine, as an ingredient in alterative decoctions, but never in 

 veterinary practice. The resin, commonly called (j^im guaiacum, 

 is sometimes used as an alterative. Farriers employ it also in 

 what they suppose to be rheumatic lameness, but, I believe, 

 without any advantage. 



The dose of gum guaiacum is from half an ounce to six 



drachms. 



When guaiacum is adulterated with common resin, if a por- 

 tion of it be thrown into lire, an odour of turpentine will imme- 

 diately be emitted. 



GUINEA PEPPER. See Cayenne Pepper. 



QUM. — Gummi. There are various kinds of gum, which 

 may be distinguished by their solubility in water, and by form- 

 ing therewith a mucilage. The principal are, gum arable, gum 

 tragacanth, and Indian gum. The first two are the best. Gum 

 dissolved in water makes a useful drink in inflammatory com- 

 plaints of the bowels, kidneys, bladder, and lungs. 



GUM RESINS. — Gummi Resina. These seem to be com- 

 pounds of resin with extractive and essential oil, and probably 

 some other hitherto undiscovered principles. Those which are 

 official are gum ammoniac, scammony, galbanum, assafoetida, 

 myrrh, gamboge, sagapenum, olibanum. 



HARTSHORN. — Comua Cervi. The horns of stags do not 

 materially differ from bone, except in containing a larger quan- 

 tity of cartilage. On boiling they yield a great deal of jelly, 

 which is more readily extracted when they are crushed or cut 

 into shavings : by distillation they yield ammonia and animal oil. 



Hartshorn, Spirit and Salt of. See Ammonia. 



HELLEBORE, BLACK AND WHITE. — iZ^//eion/5 

 Niqer. Veratrum. Black hellebore, is a native of Austria, the 

 Apennines, and Italy ; white hellebore, of Greece, Italy, Switzer- 

 land, and Russia. They both act as drastic cathartics and 

 emetics on the human frame, producing, in large doses, vertigo. 



