20 VELOCITY OF REACTIONS 



a satisfactory explanation has been discovered, it 

 is natural to apply it to the corresponding bio- 

 chemical problem, which thereby becomes eluci- 

 dated. Now it has been found in so many cases 

 that the laws of general mechanics, those of the 

 indestructibility of matter and energy and those of 

 osmotic pressure, are absolutely as valid for living 

 as for dead matter, that many scientists regard it 

 as an evident truth that life is in reality only a 

 form of matter and motion. Therefore it is often 

 maintained that living matter has developed from 

 common matter, notwithstanding that no experi- 

 mental proof has been given for this assertion. It 

 was a great merit of Tyndall to show experi- 

 mentally that everywhere where life was observed 

 to grow up it was caused by germs originating from 

 living organisms. 



It is necessary in this question to keep the 

 golden middle course, not to assert as self-evident 

 anything which has not been demonstrated, but 

 also not to deny the possibility of an agreement 

 between the laws in the two said domains before 

 a very earnest effort has been made to reconcile 

 them. 



Biochemistry is of very ancient origin. In 

 reality we may count as biochemical a great many 

 of the experiments of the iatro-chemists, who sought 

 to apply chemical principles to the elucidation of 

 vital processes. Francis de la Boe Sylvius 

 discovered that the arterial blood differs from the 

 venous blood through its content of some of the 



