EXPERIMENTS ON THE METALS FROM THE FlXfcD ALKALI9. 337 



metal consumed; and when sodium is burnt in a similar 

 manner, about a cubical inch is taken up for ev?ry grain*. 

 The alkalis so formed are only imperfectly fusible at a red 

 heat; and do not, like the easily fusible alkalis, give indi- 

 cations of the presence of moisture. 



Mr. d'Arcet has shown by some very well conducted in- Potash and soda 



onirics, that potash and soda + , in their common state, cort- contam muctt 

 1 ■ ' r ' « water. 



tain a considerable proportion of water ; and Mr. Berthol- 



lct concludes, that 100 parts of potash, that have been kept Potash loses its 



for some time in fusion, contain 13*89 parts of water, which water when 



\ combining with 



i v s lost when the alkali enters into combination with muriatic muriaticacid. 



acid ; and the same sagacious observer, from some very 



minute experiments, infers, that muriate of potash, which 



has been ignited, contains in 100 parts 66-66 potash and 



33*34 muriatic acid, a determination which diifers very 



little from that of Bucholz. 



To determine the relation of the dryness of the potash, Potassium con-- 



formed from potassium, to that which has been considered verted mto 



..«i«-. *i * . . Potash upon 



as freed from the whole or the greatest part of its water, in the surface of 



muriate of potash, I made several experiments. I first at- nu,riatic acid » 

 tempted to convert a certain quantity of potassium into potash, 

 upon the surface of liquid muriatic acid; but in this case tlie 

 heat was so intense, and hidrogen holding potassium in solu- 

 tion was disengaged with so much rapidity, that there was a 

 considerable loss of alkali ; yet even under these circum- 

 stances I obtained from 10 parts of potassium 17-5 of dry 

 muriate of potash. The most successful and the onlymodo 

 which I employed, that can be entirely depended upon, Mas and in muriatic 

 that of converting potassiqpi into muriate of potash in mu-?5 id St- 

 riatic acid gas. I shall give the results of two experiments 

 made in this manner : 5 grains of potassium, inserted in a 

 tray of platina, were made to act upon 19 cubical inches of 

 muriatic acid gas, that had been exposed to muriate of lime; 

 by the application of a gentle heat, the potassium took fire, 



* The quantities of gas given out by the operation of water are 

 in a similar ratio. See page 43 of the last Bakerian lecture [Journal 

 vol. xxiii, p. 245], and page 330 of this paper. 



f Annaks de Chimie. Nov. 1808, page 175 ; or Journal for Sep- 

 tember. 



Vol. XXVI. Supplement. Z bruat 



