On definite Proportions. 40f 



53-66 of potass, with one pnrt of water; or 100 parts of 

 sulphuric acid are saturated hy 1 18-33 of potass. Now, if 

 the 100 parts of sulphuric acid rt-quire in the 118-3i of 

 potass, according to the foregoing analysis, 20*29 of oxy- 

 gen, 100 parts of potass must consist of 17" 132 oxygen 

 and 82-848 of potassium. 



From five grammes of melted muriate of potass, dissolved 

 in water and precipitated by nitrate of silver, I ohlained 

 9-575 gr. of fused horn silver. Rose obtained from 100 

 grains of this muriate igiy of horn silver; which exactly 

 agrees with u)y experiment. Consequently the muriate oj 

 potass consists of 



Muriatic acid . . 55-81 100 



Potass 64-19 179 



Now, if 100 parts of muriatic acid suppose in these 179 

 parts of potass 30-49 of oxygen, 100 parts of potass must 

 consist of 1703 oxygen and 8!2-97 of potassium. 



The difference between the results of the calculation and 

 of the experiment amounts to somewhat less than one per 

 cent, and I have good reasons for considering that of the 

 calculation as the more accurate. Consequently potasi 

 consists of 



Potassium.. 82-97 100-000 



Oxygen 17-03 20-525 



XV. Soda. 



The bases of potass and soda are, according to Davy's 

 excellent investigation, but little different, consequently 

 they must be affected nearly in the same manner by the 

 operation of collecting them in quicksilver by means of 

 the electrical pile. The most material differences that I 

 have ot)served are the following. 



a.) The caus'.ic soda is less readily decomposed than the 

 potass, since the solution of soda is not so easily concen- 

 trated, and crystallizes sooner. 



L) 'Ihe amalgam of sodium does not crystallize, and the 

 appearance of the quicksilver is little changed, until it is 

 strongly impregnated with it: but then the sodium forms 

 sharp and silvery vegetations, which, as the proportion ot 

 the sodium to the mercury increases, assume a leaden gray 

 colour, and the form of a cauliflower, exactly like the base 

 of ammonia, which attaches itself to an iron wire covered 

 with amalgam at the point. In the open air, its surface 

 becomes moist much sooner than that of the amalgam of 

 potass; and as soon as one porticui of the solution oF soda 

 has been wiped away, another appears in increasing quan- 

 tity. 



