LECTURE II 



CONCERNING THE GENERAL CHEMISTRY OF LIFE PHENOMENA 



i. HISTORICAL REMARKS 



TO-DAY every one who is familiar with the field of chemical biology 

 acknowledges the fact that the chemistry of living matter is not spe- 

 cifically different from the chemistry of the laboratory. We owe the 

 certainty of this fact essentially to three publications, which may be 

 mentioned briefly. The first contained the proof furnished by Lavoi- 

 sier and La Place in 1780, that animal heat is produced by a process 

 of slow combustion, and that for a certain amount of heat produced 

 a certain amount of oxygen is consumed in the production of CO2. 

 A measurement of the quantity of COs formed and the amount of heat 

 produced gave approximately identical results in the case of a burning 

 candle and a living guinea pig.* 



A second step in this direction was taken when Woehler showed 

 that an organic substance like urea, which is a product of metabolism, 

 can be made artificially in the laboratory. "j" To-day so many of the 

 compounds produced in the living body can be produced artificially 

 that we can hardly understand that in 1828 Woehler's discovery was 

 considered sensational. 



The discovery of Lavoisier and La Place left a doubt in the minds 

 of scientists as to whether after all the dynamics of oxidations and of 

 chemical reactions in general is the same in living matter and in inani- 

 mate matter. The oxidation of food stuffs could indeed be imitated 

 outside the body, but only at such temperatures as were incompatible 

 with life; phenomena of digestion could be imitated, but only with 

 the aid of acids too strong for life to continue. The way out of the 

 difficulty was shown in a remarkable article by Berzelius.^ He pointed 

 out that in addition to the forces of affinity, another force is active in 



* Lavoisier et De la Place, Memoire sur la Chaleur, 1780. (Euvres de Lavoisier, Vol. 2. 

 (Also in Ostwald's Klassiker der Naturwissenschaften, Nr. 40.) 



f Woehler, Ueber kunstliche Bildung des Harnstoffs. Poggendorfs Annalen, Vol. 12, 

 p. 253, 1828. 



I Berzelius, Einige Ideen iiber eine bei der Bildung organischer Verbindungen in der 

 lebenden Natur wirksame aber bishtr nicht bemerkte Kraft. Berzelius u. Woehler, Jahres- 

 bericht, 1836. 



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