CJHEMICAL achievement — PAULING 231 



cation of this new method in organic chemistry has been to the manu- 

 facture of high polymers, such as the new fibrous and plastic 

 substances, which were synthesized in consequence of predictions of 

 their properties made upon the basis of considerations of molecular 

 structure. 



The methods used by the organic chemist become more powerful 

 from decade to decade. He now has at hand techniques of very high- 

 pressure hydrogenation, the use of catalysts specific to certain reac- 

 tions, powerful techniques of separation such as chromatographic 

 analysis and molecular distillation, and new physical methods for 

 structural studies such as X-ray diffraction and spectroscopy. A 

 very interesting example of the interrelation between organic chem- 

 istry and other fields was provided during the war by the concerted 

 attack on the problem of the structure of penicillin. The organic 

 chemists who were working on the problem found it impossible to 

 determine the correct structure by the conventional methods, because 

 the molecule has some structural characteristics that had not appeared 

 before in any known substances, and it remained for physical chemists 

 and physicists, using the techniques of X-ray diffraction and infrared 

 spectroscopy, to determine the structure for them, 



CHEMISTRY IN RELATION TO BIOLOGY AND MEDICINE 



It is the field of chemistry in relation to biology and medicine in 

 which most striking progress has been made in recent decades, and 

 which offers the most promise for the future. Biologists now are 

 becoming chemists ; they isolate vitamins, hormones, enzymes, acetyl- 

 choline in nervous processes, histamine in anaphylaxis and allergic 

 responses, plant-growth factors, wound-healing substances, flowering 

 substances, substances to hold the fruit on the trees and to ripen the 

 fruit after it has left the trees. No longer is it possible for a chemist 

 to achieve a feeling of superiority to the biologist simply by quoting 

 some complex chemical formulas — nor, indeed, for the physicist to 

 overcome the chemist by quoting some complex mathematics. 



And in medicine, as in biology, a new future is drawing near — a 

 future of great progress through ever closer cooperation with the 

 basic sciences. There has been great progress in medicine during the 

 past century. In 40 years the mean expectancy of life has increased 

 from 49 to 65 years. Mortality from childhood diseases — diphtheria, 

 scarlet fever, whooping cough — has decreased in 25 years to 10 percent 

 of its previous value. Other infectious diseases are in the main well 

 under control by vaccines, serums, the sulfa drugs, and now penicillin. 

 Shakespeare mentioned "the rotten diseases of the south, the guts- 

 griping, ruptures, catarrhs, loads o'gravel i' the back, lethargies, cold 



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