49 ^ 
Sir H. Davyds further Experiments 
mitted a little oxy-potassame, and caused it to give off oxygene 
by beating it: as soon as the calcareous compound was fused 
in contact with oxygene, it instantly emitted iodine, and lime 
was formed on the surface. 
The compound formed from hydroionic acid and baryta is 
an acrid bitter substance, very similar in its taste to harytane, 
(fused muriate of baryta,) not decomposable when heated to 
whiteness unless oxygene is present, but when it is heated in 
contact with oxygene, oxygene is absorbed, and a part of its 
iodine expelled. 
Magnesia dissolved in hydroionic acid without effervescence, 
and the solution evaporated gave a solid substance, having a 
taste very similar to muriate of magnesia. Like that salt, it 
partly lost its acid by a red heat ; but a portion remained not 
decomposable out of the contact of air, but which instantly 
afforded iodine when heated in contact with oxygene. 
I dissolved glucina, ittria, and zircona in the hydroionic 
acid; they formed neutral saline compounds. The compound 
of hydroionic acid and glucina was less soluble and more as- 
tringent in taste than the muriate of glucina, and was entirely 
decomposed when heated in the open air, affording hydroionic 
acid and iodine. 
The compound formed from ittria was more soluble, and 
highly astringent ; that formed from zircona astringent, with 
more of bitterness. Both these salts were decomposed when 
heated in the atmosphere at a low red heat ; a smell of hy- 
droionic gas was perceived, iodine was produced, and the earths 
remained. 
3. I mentioned, in a note dated Montpellier, Jan. 10, (con- 
taining a correction for my last communication to the Society,} 
