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duced by chemical synthesis, which is undoubtedly true 

 of the large majority of living species, but may not be 

 true of the simpler bacterial forms of life, such as the 

 iron and sulphur bacteria and the amoebae. Recent ex- 

 periments with tobacco leaf virus seem to show that life 

 in its simplest forms is a function of certain kinds of pro- 

 tein molecules, and we have direct experimental evidence 

 in the identity intervals of X-ray diffraction patterns 

 that the ultimate structural units in protein molecules 

 cannot be much more complex than the ordinary mole- 

 cules of organic chemistry. In fact, from what has al- 

 ready been explained, it appears that the protein mole- 

 cule is but little more than a polymerization system of 

 diketopiperazine rings. The stability of proteins against 

 heat and chemical treatment is also indicative of a com- 

 paratively simple chemical structure, the proteins being 

 merely denatured or coagulated but not destroyed unless 

 the treatment is very severe. 



Although there seems to be no valid reason why it 

 should not be possible to produce living matter by chem- 

 ical synthesis, nevertheless there exists an emotional prej- 

 udice against all efforts in this direction, which is prob- 

 ably the reason for such a deplorable scarcity of accred- 

 ited experimental investigation — and what is still more 

 unfortunate, this prejudice does not come exclusively 

 from the laity, but also from scientists of high standing. 

 It is therefore not surprising that there has been so little 

 progress in this important branch of science, because 

 scientists can hardly be expected to spend their time and 

 energy on enterprises which would precipitate upon 

 them the wrath and ridicule of those on whom they must 

 depend for their livelihood, especially when the results 

 of their investigations would probably be denied publi- 

 cation in any of the accredited scientific magazines. It 

 will not be necessary to make any comments as to where 

 this prejudice originates. As stated by Oscar Riddle of 



