CHEMICAL METAMORPHOSIS. 289 



of a compound radical, as carburetted hydrogen, may be 

 replaced by chlorine, equivalent for equivalent, and 

 form a chloride of carbon, which being constructed on 

 the same type as the original, will have the same general 

 laws of combination. 



Under the influence of these laws, all the combinations 

 which we discover in nature take place. The metals, 

 and oxygen, and sulphur, and phosphorus unite. The 

 elements of the organic type, entering into the closest 

 relations, give rise to every form of vegetable life. The 

 acids, the gums, the resins, and the sugar which plants 

 produce ; and those yet more complicated animal sub- 

 stances, bone, muscle, blood, and bile ; albumen, casein, 

 milk, with those compounds which, under the influence 

 of vital power, resolve themselves into substances which 

 are essential to the existence, health, and beauty of the 

 animal fabric, are all dependent on these laws. But 

 these metamorphoses must be further considered in our 

 examination of the more striking cases of chemical 

 action. The changes which result from organic combi- 

 nation are so remarkable, and withal they show how 

 completely the whole of the material world is in sub- 

 jection to chemical force, and every variety of form the 

 result of mysterious combination, that some particular 

 reference to these metamorphoses is demanded. 



In nearly all cases of decided chemical action, all 

 trace of the characters of the combining bodies dis- 

 appear. We say decided chemical action, because, 

 although sulphuric acid and water combine, and salts 

 dissolve in water, we may always recognize their 

 presence, and therefore these and similar cases cannot 

 be regarded as strict examples of the phenomena under 

 consideration. 



Hydrogen and oxygen, in combining, lose their gaseous 

 forms, and are condensed into a liquid water. Sul- 

 phuric acid is intensely sour and corrosive; potash is 

 highly caustic ; but united they form a salt which is 



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