256 ALKALIES. 



first, and then more oxygen is absorbed, and the peroxide is generated. 

 The color of this oxide is yellowish green or orange; it is fusible ; 

 a non-conductor of electricity, and when thrown into water, it gives 

 out its excess of oxygen. 



Its composition according to Davy, is sodium, - 75 



oxygen, - 25 



100 



Its constitution is stated to be 1 proportion of sodium 24, and 1J 

 of oxygen =12 = 36, but as this introduces a fraction, it is probable 

 that our knowledge is not precise. 



The peroxide acts upon most combustible bodies with deflagration. 

 According to some, the peroxide is composed of two proportions, of 

 Sodium, 48 



Oxygen 3, - =24 



72 would 



then be its equivalent or representative number ; of the truth of this 

 view, there seems to be no direct proof. 



5. POWERS OF COMBINATION. 



They are very extensive, like those of potassium ; to which how- 

 ever it yields an energy of affinity, as is evident in the case of the 

 decomposition of common salt by potassium. 



6. POLARITY. 



Like potassium, it is attracted to the negative pole in the galvanic 

 series, and in this way it was first discovered. 



7. DIFFUSION. 



Sodium exists very extensively in the carbonate, sulphate, muriate 

 and other forms of soda salts ; it is found in some plants, especially 

 marine ones, and in many stones and rocks. 



Remarks. The great prerogative of sodium is to attract oxygen, 

 in which function, it is inferior only to potassium. Both these re- 

 markable bodies are endued with such a degree of activity, and their 

 chemical relations, are so numerous, as almost to realize the brilliant 

 suggestion of their illustrious discover,* that they approach to the char- 

 acter of the imaginary alkahest of the ancient alchemists. Their dis- 

 covery has placed in our hands new means of investigation, and of 

 beautiful and splendid experiment. Nothing could be more unex- 

 pected, than that common salt and sea weed should contain a metal, 

 or wood ashes another. In the present state of our knowledge, we 

 must regard potassium and sodium as elements. As they exist 

 abundantly in minerals, we can understand how, in the processes of 



* Applied by him more particularly to potassium. 



