390 The Rev. S. Haughton's Account of Experiments to 



There is one other soui-ce of error which may arise, and which 

 can be easily avoided. It is the following : that if a solution of 

 the hypochlorite of soda alone, or standing over mercury, be 

 exposed to the light for several days, it will very gradually evolve 

 a minute quantity of oxygen, which shows that in determining 

 urea we should not allow the expei'iment to go on for too long a 

 time ; but if left for a day, or even two, it will scarcely make any 

 appreciable effect on the quantity of gas evolved in testing for 

 m-ea. 



The reaction which appears to take place in the process seems 

 to be the following. The hypochlorite of soda acting on the 

 urea gives rise to the formation of carbonic acid, water, and 

 chloride of sodium, together with the evolution of nitrogen gas. 

 Thus 



Urea. 3 Hypochlorite soda. 



C^H^.N^.O^. 43(Cl,O.NaO) = 2CO= + 4HO + 3Cl.Na. + N5. 



The nitrogen is evolved and the carbonic acid is absorbed by 

 some of the hypochlorite of soda in excess, for I find that this 

 salt absorbs carbonic acid very quickly without evolving any 

 other gas; and I failed in several experiments to detect the 

 smallest portion of carbonic acid in the gas produced by acting 

 on urea, though I have always noticed the presence of a very 

 minute quantity of oxygen in the nitrogen gas. These appear 

 from my experiments to be the changes produced ; but this part 

 of the subject I have not as yet minutely examined, and my expe- 

 riments have hitherto been made on healthy urine ; I have, how- 

 ever, ascertained that several of the substances found in urine 

 during disease, as for example, sugar, albumen, bile, and excess 

 of urinary colouring matter, produce scarcely any effect on the 

 results obtained by this new method of determining the quan- 

 tity of urea in the urinary secretion. 



LXI. Account of Experiments to determine the Velocities of the 

 Rifle Bullets commonly used. By the Rev. Samuel Haughton*. 



THE following experiments were made for the purpose of 

 ascertaining the reason of the alleged inferiority of the 

 belted spherical bullet, used with the two-grooved rifle, as com- 

 pared with elongated bullets of different kinds. The guns com- 

 pared are the following : — 



1. A two-grooved rifle ; length 31*50 inches; diameter 0* 66 

 inch ; one turn in 4 feet. 



2. The regulation Minie rifle; length 39 inches; diameter 

 069 inch. 



* Communicated bv the Author. 



