BEGINNINGS OF MODERN CHEMISTRY 



" Nature is at present in a state of equilibrium, which 

 cannot have been attained until all the spontaneous 

 combustions or oxygenations possible in an ordinary 

 degree of temperature had taken place. ... To illus- 

 trate this abstract view of the matter by example : Let 

 us suppose the usual temperature of the earth a little 

 changed, and it is raised only to the degree of boiling 

 water; it is evident that in this case phosphorus, 

 which is combustible in a considerably lower degree of 

 temperature, would no longer exist in nature in its 

 pure and simple state, but would always be procured 

 in its acid or oxygenated state, and its radical would 

 become one of the substances unknown to chemistry. 

 By gradually increasing the temperature of the earth, 

 the same circumstance would successively happen to 

 all the bodies capable of combustion; and, at the last, 

 every possible combustion having taken place, there 

 would no longer exist any combustible body whatever, 

 and every substance susceptible of the operation would 

 be oxygenated and consequently incombustible. 



" There cannot, therefore, exist, as far as relates to us, 

 any combustible body but such as are non -combustible 

 at the ordinary temperature of the earth, or, what is the 

 same thing in other words, that it is essential to the 

 nature of every combustible body not to possess the 

 property of combustion unless heated, or raised to a 

 degree of temperature at which its combustion nat- 

 urally takes place. When this degree is once produced, 

 combustion commences, and the caloric which is dis- 

 engaged by the decomposition of the oxygen gas keeps 

 up the temperature which is necessary for continuing 

 combustion. When this is not the case that is, when 



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