%^" 



DISEASES OF THE LIVER, URINARY ORGANS, ETC. 337 



deposits of the urine into calculi. "We have now come to the 

 subject of 



GRAVEL, OR STONE IN THE BLADDER. 



The latter of these terms is not popularly applied to the 

 disease until the calculi have become of considerable size, and 

 occasion extreme suffering ; but this is only an aggravation 

 of gravel. 



The origin of this most distressing complaint is to be found 

 in the kidneys rather than the bladder; for, although calculi 

 are oftener found in the latter, it is every way probable that 

 they exist there only as secondary results. According to this 

 view, they are first formed in the kidneys, and, passing to 

 the bladder when still quite small, frequently continue to 

 grow until they attain an astonishing size. Some have been 

 removed from the bladder, by surgical operations, that 

 weighed four ounces! In the human subject, ,the kidneys 

 are situated almost directly over the bladder, by which ar- 

 rangement the force of gravity acts to convey the little cal- 

 careous mass along the latter. But in the horse the case is 

 different. The passage communicating between the two or- 

 gans is very nearly horizontal, and the influence of gravity, 

 in effecting the end referred to, is hardly noticeable ; hence 

 calculi not unfrequently remain in the horse's kidneys, and 

 do great injury to those organs. In other cases, the calculi 

 pass into the bladder, and, when the urine is voided, are car- 

 ried by its current into the neck of that organ, and partially 

 or wholly close this outlet, and the stream then flows either 

 very slowly or is suppressed entirely. 



We have no certain means of detecting the existence of 

 calculi in the kidneys, and the fact can only be inferred from 

 the scantiness of the urine, when this is not traceable to any 

 trouble within the bladder, and by the general symptoms of 

 venal disease. But when these bodies are in the bladder, 

 they may be readily felt by passing the hand into the rectum 

 and pressing the fingers on the bladder, which lies immedi- 

 ately underneath. This is a sure test, if the calculi are of 

 any size whatever. 

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