A DICTIONARY. 



257 



coarser, and loses its healthy gloss ; at the 

 same time, the horse often becomes weak, 

 sweats readily upon moderate exercise, and 

 is often incapable of performing his usual 

 labor. This is more especially the case 

 with horses that have been hard worked 

 and badly fed. At both these periods it is 

 necessary to take particular care of horses, 

 and work them moderately. A horse, when 

 moulting, should not be exposed in the 

 stable to a current of air, but kept in a ven- 

 tilated stable. Warm clothing is improper. 



Mucilage. — A solution of gum, or any- 

 thing that partakes of the nature of gum. 

 Gummy or mucilaginous drinks are useful 

 in internal disease ; the cheapest is an in- 

 fusion of linseed or marsh-mallows ; but the 

 best, perhaps, is a solution of gum arable. 



Mucous Membranes. — (See Membrane.) 



Mucous. — Many of the secretions of the 

 body are of a mucous nature. 



Mucus. — A fluid secreted by mucous 

 surfaces. 



Muscle. — The parts that are usually in- 

 cluded under this name consist of distinct 

 portions of flesh, susceptible of contraction 

 and relaxation. 



Musk. — A powerful odorous substance, 

 whose medical virtues are chiefly anti-spas- 

 modic. 



Myrrh. — A gum resin of a fragrant 

 smell and bitter taste. It is given internally, 

 as a tonic, in doses of one or two drachms. 

 Tincture of myrrh is sometimes applied to 

 wounds, ulcers, and sinuses. 



Nag. — A name sometimes applied to 

 road horses, and such as have been docked, 

 in contradistinction to those that have long 

 tails, or are used in harness. 



Narcotics. — Medicines which stupefy, 

 relieve pain, and promote sleep. There 

 are, however, two different ways to effect 

 these objects, and, of course, two different 

 characters of remedies to be used for the 

 purpose. The popular method is to ad- 

 minister opium, whose natural tendency is 

 to depress the vital powers, and deprive 

 them of sensibility. All mixtures, in any 

 form, that contain opium, though soothing 

 for the present, are ultimately and surely 



33 



pernicious. The true plan is to give anti- 

 spasmodics. (See Anti-spasmodics.) 



Nares. — The nostrils. 



Necrosis. — The mortification and sepa- 

 ration of a portion of dead bone from the 

 other parts of the bone. 



Nephritics. — Medicines that act on the 

 kidneys. 



Nerving, Nerve Operation. — It con- 

 sists of cutting out a portion of the nerve 

 which supplies the foot, either just above 

 the fetlock joint, which is named the high 

 operation, or in the pastern, which is called 

 the low operation. In the former the sen- 

 sibility of the foot is supposed to be entirely 

 desti-oyed, and in the latter only partly so. 

 Dr. White observes, serious mischief, such 

 as the loss of the hoof, has sometimes fol- 

 lowed the liigher nerve operation. 



" After the division of a nerve, the ex- 

 tremities of the divided portion retract, 

 become enlarged and more vascular; but 

 especially the upper portion; and coagu- 

 lable lymph is effused, which soon becomes 

 vascular. In a few days the coagulable 

 lymph from each portion becomes united, 

 and anastomosis forms between the blood- 

 vessels ; the lymph gradually assumes a 

 firmer texture, and the number of the blood- 

 vessels diminishes, and the newly-formed 

 substance appears to contract, like all other 

 cicatrices, so as to bring the extremities of 

 the divided portions nearer and nearer to 

 each other. It is difficult to determine, 

 from an experiment on the limb of an 

 animal, the exact time at which the nerve 

 again performs its functions after being 

 divided. In eight weeks after the division 

 of the sciatic nerve, I have observed a rab- 

 bit to be in some degree improved in the 

 use of its leg ; but at the end of eighteen 

 weeks it was not perfect. When the nerves 

 of the leg of a horse are divided just above 

 the foot, they are sufficiently restored to 

 perform their functions, in some degree, in 

 six or eight weeks ; but it must be observed 

 that these nerves are only formed for sensa- 

 tion^ and it is very different with the nerves 

 of nutrition, voluntary motion, etc.; the re- 

 union is sometimes accomplished by gran- 



