on the Nature and Properties of Albumen^ Sfc, 



IT x_ ,.'. ti * ..r :. 



^5 



soda, and I now propose to continue the account of my investi- 

 gations in tiiis interesting department of organic cliemistry. 



9. From the result of the experiments ah'eady detailed 

 (7.)j it appeared probable that albumen after its coagulation 

 by alcohol was capable of partly decomposing the carbonate 

 and bicarbonate of soda. An interesting inquiry instantly sug- 

 gested itself as to whether the fluid albumen possessed a si- 

 milar property. To ascertain how far this was actually the case, 

 I mixed fresh serum of human blood, freed from fat (l.)? vvith 

 an equal bulk of a cold solution of carbonate of soda* of 

 spec. grav. r030. On the addition of the first portion of the 

 alkaline carbonate, the serum became slightly turbid, which 

 condition, however, ceased on agitation ; the mixture was then 

 placed in a flask furnished with a tube bent twice at right 

 angles and dipping into lime-water; heat was then applied to 

 the flask and continued until the mixture nearly attained the 

 boiling-point, when it suddenly swelled up so as nearly to 

 reach the mouth of the vessel, a torrent of bubbles at the same 

 instant escaping through the lime-water, which became quite 

 milky : the lime-water was then removed, and a vessel full of 

 diluted tincture of litmus substituted; the gas continuing to be 

 evolved, quickly converted the blue colour of the litmus to 

 red. This experiment proves most satisfactorily the evolu- 

 lution of carbonic acid gas by the action of albumen on car- 

 bonate of soda; and as neither the solution of the alkaline car- 

 bonate nor of the albumen separately evolved carbonic acid, it 

 follows as a necessary consequence that the albumen had been 

 a sufficiently energetic electro-negative element to expel part 

 of the carbonic acid from the soda and unite with the alkali 

 thus set free, forming an albuminate of soda. The contents of 

 the flask were quite transparent after the experiment, and ex- 

 erted a strong alkaline reaction on turmeric. I may observe 

 that, after repeating this experiment several times, I constantly 

 found the evolution of the carbonic acid to occur only when 

 the mixture had attained the boiling-point, and then to take 

 place suddenly, and almost immediately cease. 



10. Finding that albumen was able to expel par/ of the car- 

 bonic acid from the carbonate of soda, I attempted, by using 

 a considerable excess of albumen, to decompose entirely a 

 small portion of the carbonate ; but in this 1 failed altogether, 

 the albumen (like some other weakly electro-negative bodies) 

 having never, under any circumstances which have yet fallen 

 under my notice, been sufficiently energetic to expel all the 

 carbonic acid from any given portion of the alkaline carbonate. 



11. When the sesquicarbonate or the bicarbonate was 



* This solution had been previously boiled for some minutes to decom- 

 pose any bicarbonate of soda that might have accidentally been present. 



