OF THE OX. 323 



solution ; in fine, that the calculi of oxalate of 

 lime alone seemed to resist the action of these 

 chemical solutions. But it is well known that 

 they sometimes defy all lithotrite instruments, 

 and compel us to have recourse to the knife. 



These preliminary experiments over, it was 

 necessary to come to their application, and for 

 that purpose to make experiments on some 

 animals. The canine species, omnivorous like 

 ourselves, was chosen in preference. Bitches 

 were selected to be practised on ; for as their 

 urinary passages are wider and more flexible, it 

 enabled me to insert in the bladder fragments 

 of calculi already analysed, which were to 

 serve as the nuclei to the stones they were in- 

 tended to develop. 



This second assortment of animals, penned 

 up apart from each other, were supplied with 

 different modes of sustenance : some of them 

 were put upon a diet of meat only, others on 

 a farinaceous diet, and a third set on a 

 mixed course of food. These experiments 

 were being regularly followed up, when an 

 important and unforeseen event compelled me 

 to desist at the end of six months. The poor 

 animals were destroyed ; but all of them, as I 

 Y 2 



