1884.] Connexion with the Physiology of Uric Acid. 149 



decomposition when in an alkaline solution. Glycocine is shown to 

 have a very considerable power, even when in small quantities, such 

 as -j-'-g- per cent, of the solution. It was this fact which led to the 

 misinterpretation of certain phenomena in the author's paper of 

 1883 ; for it was found that in a glycocine solution no change of 

 uric acid took place ; whereas, in a solution of hippnric or benzoic 

 acid, decomposition readily ensued; and, as the influence of weak 

 alkaline carbonates was not then recognized, the destructive action 

 was attributed to these acids. 



It will be seen that, in a free state, glycocine protects uric acid, 

 but when in union with benzoic acid (in the form of liippuric acid) 

 its protective power is lost. 



The different protective powers of glucose and cane-sugar are 

 alluded to. 



Part III treats of the urine of the herbivorous mammal under 

 different conditions. It occurred to the author that, if at any time 

 the urine of such animals should lose its ordinary alkaline state and 

 become acid, at such time uric acid would probably be found. 



Twenty-five specimens of urine derived from nine different horses 

 were examined ; besides which many other specimens, from ten 

 different horses, were tested, simply to ascertain the reaction of the 

 urine. 



The tests employed to demonstrate the presence of uric acid are 

 fully described under each examination, and some of the more im- 

 portant characters of the urine are given. 



In eighteen different horses the urine was found to be acid in two 

 only, and even in these two the acidity of the urine was by no means 

 constant, as each of them passed, at times, an urine which was fully 

 alkaline in reaction. 



Many conclusions are drawn from the above observations, among 

 which it is found that the character of the food does not necessarily 

 influence the reaction of the urine ; neither does the state of 

 health ; it is a.lso found that almost all the urines had oxalate 

 deposits ; most of them contained an abundance of calcium carbo- 

 nate, and all the urines examined were rich both in urea and in 

 hippuric acid. 



Of the results brought out, by far the most interesting is that 

 which has regard to the presence or absence of uric acid ; for it is 

 shown that there is an absence of uric acid from the urine of the 

 horse, when the reaction is alkaline, as it ordinarily is, but on the 

 other hand, it is equally proved that, when the urine of the hore 

 exhibits an acid reaction, then uric acid is present in quantities equal 

 to what is found in the urine of carnivorous mammals, as the lion 

 and the tiger. 



It is also shown that the presence or absence of uric acid does not 



