1814.] Moijal Society. lAf 



2. Potassium burns, when heated in contact wiili the vapour of 

 ilie peculiar substance, with a pale blue flame. No gas was disen- 

 gaged. A white substance was formed, fusible at a red heat, and 

 soluble in water. Its taste was acrid. Sulphuric acid expelled from 

 it the peculiar substance. 



3. It combines with chlorine, and forms a yellow coloured solid, 

 soluble in water, and rendering the liquid yellowish green and very 

 acid. 



4. In oxygen, or In contact with hyperoxymuriate of potash, it 

 underwent no change. 



5. It united with iron, mercury, tin, zinc, and lead, forming 

 compounds fusible at a moderate heat, and almost all of line co- 

 lours. Tliese compounds, when placed in contact of water, imme- 

 diately evolved the respective metallic oxides. Several of them 

 were capable of uniting with potash, and forming compounds from 

 which sulpiiurie acid evolved the peculiar substance. 



6. The combination of the peculiar substance and phosphorus is 

 very analogous to phosphurane. During the combination acid 

 fumes are given out. They are similar to the acid, formed more 

 abundantly when the compound is heated in waiter. This acid is a 

 gas, rapidly absorbed by water, and combining with bases, and 

 forming peculiar salts. When mercury is heated in the acid gas the 

 same compound is formed as that produced by the direct action of 

 the peculiar substance on mercury, and hydiogen is evolved equal 

 in bulk to half the bulk of the acid gas. Potassium produces a 

 similar effect without any combustion taking place. All these, and 

 otiier phenomena of the same kind, detailed in the paper, lead to 

 the conclusion that the acid is composed of tiie peculiar substance 

 and hydrogen. 



7. It seems capable of uniting directly with liydrogen gas, and 

 of forming the new acid. 



8. It is dissolved in solution of potash, oxygen Is expelled from the 

 potash, and two new compounds are produced. One, precipitated 

 in crystals, Is a compound of the peculiar substance, potassium, and 

 oxygen. It is similar in Its properties to hyperoxymuriate of potash. 

 The other, remaining in solution, is a compound of the peculiar 

 substance and potassium. 



y. Similar results are obtained with solutions of soda and barytes. 



10. The peculiar subst;inee Is expelled from all its combinaiions 

 by chlorine ; wiiile, on the contrary, it usually expels oxygen from 

 its combinations. 



11. When the peculiar substance is dissolved In liquid ammonia, 

 a black powder precipitates, which detonates, and appears to be a 

 combination of tiie peculiar substance and azote. 



!'-'. '2*H grains of pota-^siun) are saturated by G'25 of the peculiar 

 substance. Supposing them to imite atom to atom, and that the 

 Weight of an atom of potassium is .'>, then the weight of an atom 

 of iW. peculiar substance will be 11-160: so tliat it is as heavy as 

 several of the inetals. 



K 2 



