303 



amounts of these isomerides formed in a certain period, or perhaps 

 that they are slowly eliminated, while the other antipode is taking 

 part successfully in the common physiological reaction-scheme of 

 the organism, obtained during a long period of evolution. It is 

 more a question of strongly deviating velocities, than of extreme 

 differences of quantity. If complete equilibrium could ever be 

 reached during these processes, perhaps in the end we should really 

 meet with equal or comparable quantities of both isomerides. But 

 as has already been said, such a state will never be reached, as 

 the life-process is continuously going on. 



Now Fischer supposes that the asymmetric substances in the 

 chlorophyll-grains primarily combine with the carbon-dioxide, or 

 with the formaldehyde produced from it; and the following conden- 

 sation to form sugars will then occur in an asymmetrical and 

 preferential way, because of the directing influence of the pre- 

 existing molecular dissymmetry. The products formed are used 

 up in the life-process of the plant as fast as they are made. 

 The "asymmetric forces" of Pasteur need not be looked for 

 outside the organism, for they are determined by the chemical 

 system in its cells, and these dissymmetrical influences in the 

 living organism itself far outweigh the dissymmetrical agency of 

 externally applied forces. All attempts to counterbalance or even 

 to surpass these chemical directing influences, have hitherto 

 completely failed. Pasteur himself 1 ) refers to these somewhat 

 phantastic and unsuccessful experiments, when he tried in 1854 

 to influence the particular dissymmetry of vegetable synthesis 

 by means of a clock-driven heliostat and reflector, which reversed 

 artificially the diurnal motion of the sun in the sky. 



They were unsuccessful of course : for what is this feeble influence 

 compared with the enormous power of atomic attraction? He 

 had, as has been occasionally said, still to deal with the one- 

 sided agencies in all their irresistible strength, as they were deter- 

 mined by the dissymmetry of the chemical system in the living cells 

 from the beginning of evolution. As has strikingly been remarked: 

 starting with a definite optically active compound, there is some- 

 thing analogous to "heredity" in the further progression of dis- 

 symmetrical configurations in a series of successive reactions. Perhaps 

 if the original optically active substance had been the antipode 



L. Pasteur, Revue Scientifique, (3), 7, 3, (1884). 



