Animal Secretions. 4 so, 



animals, I had deferred pursuing the application of my th?* 

 ory, until it was again brought back to my mind by finding 

 that the same thought had occurred to Dr. Young. And 

 as it has already been printed some month's in the Syllabus 

 of his Course of Medical Lectures, I had for the present re- 

 linquished all thoughts of recording conjectures, which, if 

 not well founded, might retard the progress of science. 



But since some experiments relating to the same inquiry 

 are now about to be published by Mr. Home, it may perhaps 

 be of use to add my experiment to the general stock of in- 

 formation, although I have not myself improved upon it by 

 any further consideration, and am not yet enabled to con- 

 firm the hypothesis, which it appeared to support, by any 

 new arguments. 



The experiment was conducted as follows : 



I took a piece of glass tube about three quarters of an inch 

 in diameter and nearly two inches long, open at both ends, 

 and covered one of them with a piece of clean bladder. Into 

 this little vessel I poured some water in which I had dis- 

 solved t 4tt of its weight of salt; and after placing it upon a 

 shilling with the bladder slightly moistened externally, I 

 bent a wire of zinc so, that while one extremity rested on 

 the shilling the other might be immersed about an inch in 

 the water. By successive examination of the external sur- 

 face of the bladder, I found that even this feeble power oc- 

 casioned soda to be separated from the water, and to tran- 

 sude through the substance of the bladder. The presence of 

 alkali was discernible by the application of reddened litmus- 

 paper after two or three minutes, and was generally mani- 

 fest even by the test of turmeric before five minutes had ex- 

 pired. 



The efficacy of powers so feeble as are here called into 

 action, tends to confirm the conjecture that similar agents 

 may be instrumental in effecting the various animal secre- 

 tions, which have not yet been otherwise explained. The 

 qualities of each secreted fluid may hereafter instruct us as 

 to the species of electricity that prevails in each organ of 

 the body. 



For instance, the general redundance of acid in urine, 



though 



