CHEMICAL PHENOMENA IN LIFE 



effect as proportional to the quantity of the 

 catalysing substance. So the acceleration of the 

 splitting of cane sugar by acids was found to be 

 directly proportional to the concentration of 

 the acid applied. Another difference is shown by 

 the experience that release effects in processes 

 of stimulation in plants or in animals do not occur 

 without a stimulus. But catalytic reactions, as 

 it seems, are not strictly dependent for their 

 existence on the presence of the catalyser. For a 

 series of reactions it has already been stated 

 that the reaction takes place even without the 

 catalyser being present, yet, it must be admitted, 

 slowly. 



We come to the conclusion that the catalysing 

 substance is only an accelerating agent, but not 

 an agent without which the effect does not take 

 place at all. This is very important for an exact 

 understanding of catalysis effects. If we find 

 it desirable to compare the catalyser with any 

 mechanism in an engine, we cannot compare it 

 with a releasing contrivance, but we may rather 

 find a resemblance between the effect of train-oil on 

 the smooth going of the engine and the accelerating 

 effect of a catalysing substance. 



Hitherto only accelerating catalysis has been 

 spoken of. Some effects on chemical reactions 

 have been found which seem to have the contrary 

 of an accelerating catalytic influence. The oxi- 

 dation of sulphurous acid, for example, can be 

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