84 



bladder half full of liquid, and if necessary one oiled hand may be intro- 

 duced into the rectum or vagina to assist. The resulting irritation 

 may be treated by an injection of laudanum, 1 ounce, in a pint of tepid 

 water. 



The removal of the stone in the horse is a much more difiicult pro- 

 ceeding. It consists in cutting into the urethra just beneath the anus 

 and introducing the lithotomy forceps from this forward into the blad- 

 der, as in the mare. It is needful to distend the urethra with tepid 

 water or to insert a sound or catheter to furnish a guide upon which 

 the incision may be made, and in case of a large stone it may be need- 

 ful to enlarge the passage by cutting in a direction upward and out- 

 ward with a probe-poiuted knife, the back of which is slid along in the 

 groove of a director until it enters the bladder. 



The horse may be operated upon in the standing position, being 

 simply iiressed against a wall by a pole passed from before backward 

 along the other side of the body. The tepid water is injected into the 

 end of the penis until it is felt to fluctuate under the pressure of the 

 finger, in the median line over the boue just beneath the auus. The 

 incision is then made into the center of the fluctuating canal, and from 

 above downward. When a sound or catheter is used as a guide it is 

 inserted through the penis until it can be felt through the skin at the 

 point where the incision is to be made beneath the anus. The skin is 

 then rendered tense by the thumb and fingers of the left hand pressing 

 on the two sides of the sound, while the right hand, armed with a 

 scalpel, cuts downward on to the catheter. This vertical incision into 

 the canal should escape wounding any important blood-vessel. It is in 

 making the obliquely lateral incision in the subsequent dilatation of the 

 urethra and neck of the bladder that such danger is to be apprehended. 



If the stone is too large to be extracted through the urethra it may 

 be broken down with the lithotrifce and extracted piecemeal with the 

 forceps. The lithotrite is an instrument composed of a straight stem 

 bent for an inch or more to one side at its free end so as to form an obtuse 

 angle, and having on the same side a sliding bar moving in a groove in 

 the stem and operated by a screw so that the stone may be seized be- 

 tween the two blades at its free extremity and crushed again and again 

 into pieces small enough to extract. Extra care is required to avoid 

 injury to the urethra in the extraction of the angular fragments, and 

 the gravel or jiowder that can not be removed in this way must be 

 washed out as advised below. 



When a pultaceous magma of carbonate of lime accumulates in the 

 bladder it must be washed out by injecting water through a catheter 

 by means of a force pump or a funnel, shaking it up with the hand intro- 

 duced through the rectum and allowing the muddy liquid to flow out 

 through the tube. This is to be repeated until the bladder is empty 

 and the water comes away clear. A catheter with a double tube is 

 sometimes used, the injection passing in through the one tube and 



