302 Prof. E. D. Smith on Calculous Jlffections, 



a change in the qualities and appearance of the urine gen- 

 erally indicates the approaching mischief and affords the 

 opportunity of arresting its progress. When the uric acid 

 is in excess, it occasions irritation in the urinary passages 

 and finally, a discharge of very small crystals, like red sand: 

 and when the alkaline salts predominate, a fine white and 

 sandy substance is voided.* 



A previous knowledge of the subject and a proper atten- 

 tion to these indications will generally enable us to apply 

 correct remedies and thus to destroy in the germ what 

 would be irremediable'at maturity. 



Without stopping to investigate the fact, whether there 

 may be a short and direct communication from the stomach 

 to the bladder, or whether this communication may depend 

 upon the retrograde action of the absorbents, it will be suf- 

 ficient to assert what has been proved by numerous experi- 

 ments, that the character of the urine can be changed by 

 substances, that ard taken into the stomach. Its natural 

 state of free acidity can be entirely altered and it can 

 be made obviously alkaline in its nature ; and upon this cir- 

 cumstance has been grounded the practice of administering 

 alkalies for the relief of gravelly complaints. This seems 

 to have been the practice of the ancient Greek physicians, 

 as stated in the second volume of Johnson's Animal Chem- 

 istry, and it is well known to have been that of the mod- 

 erns, from the era of Mr. Steven's celebrated lithontrip- 

 tic down to the present time. A little reflection will satisfy 

 that this mode of practice has been too empirical ; for if 

 chemical analyses have demonstrated that calculous concre- 

 tions are sometimes of opposite natures, it must be allowed 

 that the same remedy cannot be adapted to every kind. It 

 is then surely incumbent upon the physician to ascertain the 

 real nature of the case; and, from the want of knowledge 

 to do so, there can be no doubt that such diseases, instead 

 of being relieved, have often been aggravated. To this 

 difference in the constitution of calculous matter it is owing 

 that both the strong and the weak acids have sometimes 

 been used with eminent benefit; and yet the indiscriminate 

 prescription of acids would frequently produce the most seri- 

 ous injury. 



* London Medical and Physical Journal, Vol. 30, page 327, &c. 



