66 On some new Electrochemical Researches 



hour; so that there is great reason to believe, that the silex 

 had been either entirely or partially deoxygenated, and was 

 slowly reproduced by the action of the water, assisted by 

 the slight attraction of the acid for the earth. 



When the potassium was in the quantity of six grains, 

 and the silex of four grains, a part of the' result inflamed 

 spontaneously as it was taken out of the tube, though the 

 tube was quite cool, and left, as the result of its combustion, 

 alkali and silex. The part which did not inflame, was 

 similar in character to the matter which has been just de- 

 scribed, it did not act upon water, but effervesced with 

 muriatic acid. 



Potassium in acting upon alumine and glucine, produced 

 more hydrogen than could be ascribed to the moisture pre- 

 sent in the crust of potash ; from which it seems probable 

 that even after ignition, water adheres to these earths. 



The results of the action of the potassium were pyro- 

 phoric substances of a dark gray colour, which burnt, 

 throwing off brilliant sparks *, and leaving behind alkali 

 and earth, and which hissed violently when thrown upon 

 water, decomposing it with great violence. I examined the 

 products in two experiments, one on alumine, and one on 

 glucine, in which naphtha was introduced into the platina 

 tube, to prevent combustion ; the masses were very friable, 

 and presented small metallic particles, which were as soft 

 as potassium, but so small that they could not be separated, 

 so as to be more minutely examined; they melted in boil- 

 ing naphtha. Either a part of the potassium must have 

 been employed in decomposing the earths in these experi- 

 ments, or it had entered into combination with them ; 

 which is unlikely, and contrary to analogy, and opposed 

 by some experiments which will be immediately related. 



Supposing the metals of the earths to be produced in 

 experiments of this kind, there was great reason to expect 

 that they might be alloyed with the common metals, as 

 well as with potassium. Mercury was the only substance 

 which it was safe to try in the tube of platina. In all cases 

 in which the potassium was in excess, I obtained amal- 

 gams by introducing mercury, whilst the tube was hot; 

 but the alkaline metal gave the characters to the amalgam, 

 and though in the case of glucine and alumine, a white 

 matter separated during the action of very weak muriatic 



* The pyrophorus from alum, which I have supposed in the last Bakerian 

 lecture to be a compoumd of potassium, sulphur, aud charcoal, probably 

 contains this substance likewise. 



acid 



