102 BUREAU OF ANIIsIAL INDUSTRY. 



forceps. The lithotrite id 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 between 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 frag- 

 ments, and the gravel or powder 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 

 b}^ means of a force pump or a funnel, shaking it up with the hand 

 introduced 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 escaping through the other. But the advantage is more apparent 

 than real, as the retention of the water until the magma has been 

 shaken up and mixed with it hastens greatly its complete evacuation. 



To prevent the formation of a new deposit any fault in feeding (dry 

 grain and hay with privation of water, excess of beans, pease, whea.t 

 bran^ etc.) and disorders of stomach, liver, and lungs must be cor- 

 rected. Give abundance of soft drinking water, encouraging the 

 animal to drink by a handful of salt daily; let the food be laxative, 

 consisting largelj^ of roots, apples, pumpkins, ensilage, and give daily 

 in the drinking water a dram of carbonate of potash or soda. Pow- 

 dered gentian root (3 drams daily) will also serve to restore the tone 

 of the stomach and sj^stem at large. 



TJTethral calculits {stone in the urethra). — This is less frequent in 

 horses than in cattle and sheep, owing to the larger size of the urethra 

 in the horse and the absence of the S-shaped curve and vermiform 

 appendix. The calculi arrested in the ui'ethra are never formed there, 

 but consist of cystic calculi which have been small enough to pass, 

 through the neck of the bladder, but too large to pass through the 

 whole length of the urethra and escape. Such calculi therefore are 

 primarily formed either in the bladder or kidney, and have the chem- 

 ical composition of the other calculi found in those organs. They may 

 be arrested at any point of the urethra, from the neck of the bladder 

 back to the bend of the tube beneath the anus, and from that point 

 down to the extremit}" of the penis. 1 have found them most fre- 

 quently in the papilla on the extreme end of the penis, and immedi- 

 ately behind this. 



Symjytoms of urethral calculus. — The sjmiptoms are violent straining 

 to urinate, but without any discharge, or with the escape of water in 

 drops only. Examination of the end of the penis will detect the swell- 



