A DICTIONARY. 



235 



cheek, and the inside of the lower gi-inders 

 acts similarly upon the tongue, or the skin 

 connected with it. Whenever a horse is 

 observed to void unbroken oats with his 

 dung, the teeth and cheeks should be ex- 

 amined. It will often be found necessary 

 to rasp the outside edges of the upper 

 grinders, and sometimes the inner edges of 

 the lower ones. 



Demulcents. — Medicines of a mucila- 

 ginous kind, which sheath the mucous 

 membranes when they are tender and irri- 

 table, and defend them from the action of 

 what would otherwise injure them. Of 

 this kind are marsh mallows, linseed tea, 

 solution of gum arable. 



Dentition. — The act of changing the 

 teeth, which is going on from the second to 

 the fifth year. During this period, the horse's 

 mouth is apt to become tender, which ren- 

 ders it necessary to keep him for a short 

 time on scalded shorts, or boiled carrots. 



Diabetes. — An excessive discharge of 

 urine, accompanied by thirst and debility. 

 There are three outlets for the fluids of the 

 body, — the surface, the lungs, and the 

 urinary passage. When either is deficient 

 in action, one or both of the others must 

 make up that deficiency ; so, excess in one 

 produces deficiency in the others ; hence, in 

 diabetes we often find a dry skin and stare- 

 ing coat ; and in excessive perspiration, the 

 urine is scanty, whatever be the organs 

 affected or whether the one or the other be 

 excessive or diminished. The indications 

 are, to equalize the action of these opposing 

 or sympathizing surfaces, by restoring the 

 diminished secretions, and cleansing and 

 toning the organ whose action is excessive. 

 All direct efforts to produce specific effects, 

 without regard to a balance of action 

 through the whole animal, do more harm 

 than good. 



Diaphoretics. — Medicines that promote 

 insensible perspiration, or excite moderate 

 sweating. Of this class are lobelia and 

 emetics, given in infusion. 



Diaphragm, Midriff, or Skirt. — A mus- 

 cular and tendinous expansion, which divides 



the cavity of the chest from the abdomen, 

 or belly. 



DiARRHCEA, or PuRGiNG. — 111 Professor 

 Percivall's lectures on diarrhoea, he states 

 that, " for the majority of cases brought to 

 us, we are indebted to the groom, the far- 

 rier, and stable-keeper, who used to kill 

 many horses by literally purging them to 

 death. Thirty years ago, an ounce and a 

 half or two ounces of aloes, occasionally 

 combined with one or two drachms of 

 calomel, composed the common purge ; and 

 even now, among these people, nine, ten, 

 and eleven drachms are by no means un- 

 usual doses. Young horses, on their first 

 arrival in the metropolis, are all physicked ; 

 they have given to them, indiscriminately, 

 doses of aloes, every one of which would 

 be sufficient to purge two of them ; the re- 

 sult is, that the light-carcassed, irritable 

 subject is carried off" at once by superpurga- 

 tion, while another, or two, may linger in 

 misery and pain from a dysentery that will 

 end in gangrene and death, or be rendered 

 more speedily fatal by the doses of opium, 

 or some other powerful astringent, which 

 are so perniciously resorted to on these 

 occasions. There is another not uncommon 

 cause of this disease, and that is, continuous 

 and excessive exertion. After having been 

 ridden for many hours, a horse will often 

 express irritation in the bowels, by fre- 

 quently voiding his excrement, which will 

 be found to be enveloped in a slimy or 

 mucous matter, that is called by some 

 molten grease." 



DiLUTENTS. — Those substances that in- 

 crease the fluidity of the animal economy. 

 Water may be justly considered as the only 

 dilutent. 



Director. — A grooved instrument, made 

 for the purpose of conducting the knife in 

 open sinuses, and in several other opera- 

 tions of surgery. 



Dislocation. — A displacement of a 

 bone from its socket. A dislocation of the 

 fetlock joint may be replaced, and kept in 

 its position by bandages ; the horse should 

 not take any exercise until it is completely 



