22 
Mr. Davy’s Lecture on some 
of purified water was higher than the level of the saline 
solution. 
In this case, the saline matter was distant from each of the 
wires at least y of an inch ; yet alkaline matter soon appeared 
in one tube, and acid matter in the other: and in 16 hours 
moderately strong solutions of potash, and of muriatic acid had 
been formed. 
In this case of electrical transfer or attraction, the acid 
and alkaline matter seemed to be perfectly pure ; and I am 
inclined to believe that this is uniformly the case in all expe- 
riments carefully made. One of the instances in which I con- 
ceived acid most likely to be present, was in the transfer of 
magnesia from sulphate of magnesia in the positive tube, to 
distilled water in the negative tube. I examined the case, 
taking care that the distilled water was never upon a lower 
level than the saline solution : the process was continued for 
some hours, till a considerable quantity of magnesia had ap- 
peared. The connecting amianthus was removed, and muriatic 
acid poured into the tube : the saturated solution did not pre- 
cipitate solution of muriate of barytes. 
I endeavoured to ascertain the progress of the transfer, and 
the course of the acid or alkaline matter in these decompo- 
sitions, by using solutions of litmus and turmeric, and papers 
coloured by these substances ; and these trials led to the 
knowledge of some singular and unexpected circumstances. 
Two tubes, one containing distilled water, the other solu- 
tion of sulphate of potash, were each connected by amianthus 
with a small oz. measure filled with distilled water tinged by 
litmus : the saline solution was negatively electrified ; and as 
it was natural to suppose, that the sulphuric acid in passing 
