On the Composition of the Great Bhurtpoor Gun. 181 



the commencement, cause it to disappear before it could be eli- 

 minated in the urine. It is possible to conceive that, in certain 

 morbid states of the system, a process of decomposition may be 

 set up inducing a further metamorphosis in the extractive mat- 

 ters, and leading to the formation of a greater quantity of sugar 

 than can be got rid of by oxidation. Some such process may 

 perhaps serve to account for the large amount of sugar found in 

 the urine in diabetes, the origin of which is still involved in so 

 much obscurity. It is well known that in this disease hippuric 

 acid is found in the urine in much greater abundance than in a 

 state of health. Now the composition of two of the urinary ex- 

 tractive matters is such, that they may be supposed to split up 

 into sugar, hippuric acid, and acetic acid; while in the case of 

 the third it is only necessary to suppose that the acetic acid is 

 replaced by formic acid. It seems to me not improbable that 

 some such process of decomposition may take place in the body, 

 perhaps under the influence of a peculiar ferment, and that the 

 extractive matters are the immediate source of the sugar occur- 

 ring in the urine in this disease, the remote source being of 

 course the tissues themselves. The saccharine state of the urine, 

 which, according to Dr. Pavy, is produced by the injection of 

 acids into the circulation, may possibly be caused by the action 

 of the acid on the urinary extractive matters, as well as on the 

 glycogene of the liver. 



I will not trouble you with any further speculation on the 

 subject, as my experiments, which have suffered considerable in- 

 terruption from unforeseen circumstances, will, I hope, soon be 

 brought to a conclusion. On the present occasion I merely 

 wish to announce the fact that ordinary healthy urine contains 

 substances which, by decomposition with acids, yield among 

 other products a species of sugar, and that these substances are 

 simply the extractive matters always contained in the secretion. 

 I am, Gentlemen, 



Your most obedient Servant, 

 Kersall, Manchester, E. ScHUNCK. 



January 27, 1862. 



XXVI. On the Composition of the Great Bhurtpoor Gun, stationed 

 on the Royal Artillery Parade Ground, Woolwich; and of 

 some other interesting Cannon. By F. A. Abel, F.R.S.* 



IN 1828 the largest gun taken, shortly before, at Bhurtpoor, 

 and which had been presented to George IV. by Viscount 

 Combermere and the forces engaged in the capture of that 



* Communicated by the Author. 



