342 



The mucus contained in saliva in expectorated fluids, and in that 

 from the oyster, were first examined ; but since nitrate of silver and 

 acetate of lead, which have been supposed to detect mucus, were 

 found to act principally on the salts contained in them, it became 

 necessary to employ other means for the removal of the salts ; and 

 the voltaic apparatus was applied for the purpose of extracting the 

 alkalies at one pole, and the acids at the opposite. But there oc- 

 curred a phenomenon that was wholly unexpected ; as a considerable 

 coagulation of albumen took place at the negative pole, which Mr. 

 Brande (at the suggestion of Mr. Davy) is inclined to ascribe to the 

 separation of alkali with which it was combined, and to which its 

 solubility was owing. 



It is observed, in confirmation, that when an egg is boiled for some 

 time in water, the liquid becomes alkaline to tests, and still deposits, 

 by electrization, a small quantity of albumen, which the alkali re- 

 tains in solution. 



The coagulation of albumen by acids is also ascribed to their su- 

 perior affinity for the alkali. 



For discovering the nature of the saline ingredients, the water in 

 which some white of egg had been boiled and macerated, was elec- 

 trified by a powerful battery, through the medium of a cup of water 

 on each side. After the process had continued for one hour, the 

 fluids were examined ; that on the negative side contained a quan- 

 tity of soda nearly pure, and that on the positive side a small quan- 

 tity of albumen, with a little muriatic acid, but not enough to satu- 

 rate the alkali. 



The same means of analytic investigation being applied to other 

 fluids, detected larger quantities of albumen than were discoverable 

 by heat alone ; as in saliva, in the mucus from the oyster, the mucus 

 from the trachea, in bile, in milk, and in the liquor of Amnios : and 

 hence the author is led to doubt whether mucus may not be a com- 

 pound of albumen, either with muriate of soda or with excess of soda. 



Hints on the Subject of animal Secretions. By Everard Home, Esq. 

 F.R.S. Communicated by the Society for the Improvement of Ani- 

 mal Chemistry. Read June 22, 1809. [Phil. Trans. 1809, p. 385.] 



The separation, by electric powers, of substances chemically united, 

 suggests the possibility, that since the same power is known to exist 

 in the torpedo and electrical eel, it might be the means by which 

 secretion in all animals is effected. 



Since in these fish the abundance of nerves connected with the 

 electrical organs proves that this power resides in them, and since 

 the arrangement of many nerves in animal bodies has evidently no 

 connexion with sensation, it seems not improbable that these may 

 answer the purpose of supplying and regulating the organs of secre- 

 tion. 



With a view to determine what changes could be produced in the 

 blood similar to secretion, Mr. Brande applied the power of twenty- 



