JAUNDICE, OR THE YELLOWa 828 



contains. The cystic duct is large at its union with the bladder ; it is 

 a continuation of the neck of the bladder ; and the gall-stone may- 

 be easily pressed into the commencement of the tube : but it has 

 scarcely entered it before its passage is obstructed by the folds of the 

 inner coat of of the duct. These assume a semilunar form, with the 

 edges projecting toward the bladder, and they act as partial valves, 

 retarding the progress of the bile, so that it may not be all pressed 

 out at once, but gradually escape as the process of digestion may 

 require. 



The gall-stone being thus impacted, violent spasmodic action takes 

 place in the muscles of the duct, occasioned by the irritation of its 

 continued pressure. It is fortunate, however, that, although the 

 muscles of these ducts act with some power, the obstruction is usu- 

 ally with no great difficulty overcome. The duct distends ; as it 

 distends, these valvular folds lie closer to the sides, and no longer 

 oppose the passage of the calculus, which is pressed on until it 

 reaches the common duct. The caliber of this tube is larger, and, 

 unless the calculus is of considerable bulk, no farther difficulty occurs 

 until it reaches the opening into the duodenum, which being situated 

 in the centre of a muscular prominence, acting as a valve, and pre- 

 venting the passege of all matters whether fluid or sohd from the 

 intestine into the ducts, a new difficulty is opposed to the pro- 

 gress of the gall-stones, and there is some return of pain, and in 

 a few cases the pain is evidently more intense than in the early 

 stage. At length this sphincter muscle of the duodenum dilates ; 

 the calculus enters the intestinal canal ; the pain ceases, and the 

 natural color of the skin returns. In this species of jaundice, we 

 have, in addition to the yellow skin, the heaving of the flanks, the 

 hard concentrated pulse, the diminished appetite, the insatiable thirst, 

 and the other symptoms of fever. Then, too, we have the alter- 

 nate coldness and heat of the ears, the roughness of the coat, the 

 urine becoming first of a transparent yellow, and then opaque red, 

 saffron-colored, or brown, and the sediment brown. The bowels 

 are constipated, the faeces seldom evacuated, and, when appearing, 

 are hard and black. 



Bleeding is now clealy indicated, and that until the animal be- 

 comes faint. During this partial sympathy, the muscles of the duct 

 may cease their spasmodic constriction, and the calculus may pass 

 on. To this should be added powerful purgation, consisting of doses 

 of a pound and a half each of Epsom salts, or of a pound of the 

 salts, with ten grains of the Croton Tiglii ; the medicine being re- 

 peated once in six hours, until purging is produced. Mashes should 

 be given, to hasten and increase the action of the physic, and the 

 beast should, if possible, be turned out to grass during the day, and 

 taken up at night." Opium or digitalis, and particularly the latter, 

 may be given, in dos^ of half a drachm of either, with a view to 



