ON CALCULUS VESICLE 151 



SUPPLEMENT TO THE FOREGOING DISSERTATION. 

 BY T. BERGMAN. 



Without knowing anything of Mr. Scheele's analysis of 

 the calculus vesicle, I was employed at the same time upon the 

 same subject. My experiments lead nearly to the same con- 

 clusion, viz. that these animal stones consist of a concrete 

 acid. There are, however, some circumstances in which 

 they differ from those of Mr. Scheele. Perhaps the calculi 

 on which we made our experiments were really different 

 in their nature ; but as the differences I remarked were 

 constant with all the calculi on which I made experiments, 

 I thought it worth while to communicate them to the 

 public, especially as they relate to a matter so interesting 

 to mankind. 



I could not succeed in entirely dissolving stones of the 

 bladder or kidney, either in distilled water or in nitrous 

 acid ; though it is true that the undissolved part is the 

 less the more finely the calculus has been previously 

 pounded ; but even in this case a part remains undissolved, 

 as appears clearly when the experiment is made in a small 

 cucurbit; so that, after the mass is cooled, the undissolved 

 part may settle at the bottom in one place. This appears 

 in the clearest manner, if small pieces or small calculi, of 

 a few grains weight only, be put into a superabundant 

 quantity of menstruum, and be kept in a degree of heat 

 very near to that which makes water boil. Here it will 

 be observed that the greatest part of the piece is dissolved, 

 but that at the same time some small white spongy 

 particles remain, upon which water, spirit of wine, acids, 

 or caustic volatile alkali, have no sensible effect. If the 



