220 Electrochemical Researches on 



water, the inflammable body is less compounded than the 

 uninflammable substance resulting from its combustion. 



Other 



wire which closed the tube containing the potash, between that alkali and 

 the metal. 



As the potash came in contact with the iron, gaseous matter was developed, 

 which was received in a proper apparatus, and though some of it was lost by 

 pausing through the potash into the atmosphere, yec nearly half a cubic foot 

 was preserved, which proved to be hydrogen. In the tube were found two 

 products, one in the quantity of a few grains, containing potassium, combined 

 with a small quantity of iron, and which had sublimed in the operation, and 

 the other, a fixed white metallic substance which consisted of an alloy of iron 

 and potassium. 



The first of these substances burnt when thrown upon water; and in its 

 other characters resembled pure potassium, except that its specific gravity was 

 greater, its colour less brilliant, and when it tarnished in the atmosphere, it 

 became of a much deeper colour than pure potassium. 



Now potash that has been ignited, is the purest form known of this ah- 

 kali ; but on M. M. Gay Lussac's and Thenard's theory, this potash must 

 contain water, not only sufficient to furnish hydrogen to metallize the alka- 

 li, but likewise the quantity disengaged : dry potash, then, as it is procured 

 in our experiments, must on this theory be a compound, containing a con» 

 sider.ible quantity of matter which can furnish hydrogen ; and what 

 would be its form or properties if deprived of this matter we are wholly un- 

 able to judge, which brings this question to the general question discussed in. 

 the text. 



Potassium I find may be produced readily from dry ignited potash in elec- 

 trical experiments ; and the result of the combustion of potassium in oxygen 

 gas is an alkali, so dry that it produces violent heat, and ebullition when 

 water is added to it. 



In M. M. Gay Lussac's and Thenard's experiment on the action of potas- 

 sium on ammonia, the hydrogen disengaged in the first process, and that ex- 

 isting in the ammonia disengaged in the second process, exactly equals the 

 whole quantity contained in the ammonia. But there is no proof of any hy- 

 drogen bwing disengaged from the potassium, for the ammonia lost is not ge- 

 nerated, nor potash formed, but by the addition of a substance, consisting of 

 oxvgeii and hydrogen ; and as the three bodies concerned in this experiment 

 are potassium, ammonia, and water, the result oughi, to be potash, ammonia, 

 and a quantity of hydr< igeh, equal to that evolved by the mere action of water 

 on potassium, which is said to be the case. 



Even if there were no other proofs, the chemical properties of potassium 

 are so wholly unlike chose that might be expected front a compound of potash 

 and hydrogen, that they are almost sufficient to dtcide the question. Potas- 

 sium acts upon water with much more energy than potash, and produces much 

 more heat in it, and yet if a compound of hydrogen, the affinity of potash for 

 water must be diminished by its affinity for hydrogen, to say nothing of the. 



quaatitv 



