Celebration of the Fiftieth Anniversary. Ixv 



larger than Mulder assumed and the idea became in time 

 pretty well established that these bodies are, in fact, so com- 

 plex as to be beyond our power of reconstruction or analysis. 



However, this general view did not shut out all investiga- 

 tion as to the real constitution of the albumins, and in the 

 last twenty years a mass of evidence has been accumulated 

 which shows that even the largest of the protein molecules 

 must be built up by the combination of a number of compar- 

 atively simple complexes, among which certain amino acids 

 are the most important. With this much gained the next 

 step was to attempt to unite these groups by synthetic reac- 

 tions, one by one, and thus build up the great protein bodies 

 of high molecular weight. The idea was a daring one and its 

 practical realization seemed for a time hopeless. However, 

 the problem was at last successfully attacked by two German 

 chemists, Fischer and Curtius, working independently and a 

 remarkable result has been reached. These men have devel 

 oped methods by which the constituent groups may be grad- 

 ually linked together and already they have secured synthetic 

 products of relatively great molecular weight, possessing 

 many of the protein properties. The series of bodies made 

 by Fischer are known as polypeptides, and the whole achieve- 

 ment must be looked upon as of the highest scientific import- 

 ance. The proteins have long been regarded as the most 

 complex of organic structures and the successful solution of 

 this problem, which now appears in sight, will go far toward 

 clearing out the " Rumpelkammer " of organic chemistry, 

 which fifty years ago was the most crowded chamber of our 

 chemical edifice. 



In the study of chemical function, the second main direc- 

 tion in which progress has been made, the advances have 

 been even more remarkable. The change has been so marked 

 here as to^constitute almost the birth of a new science. We 

 need not go back fifty years to reach a time when chemistry 

 was spoken of as " a science of the second rank," by our col- 

 leagues in physics, mathematics and astronomy. The older 

 chemistry knew little of mathematics ; but that condition is 

 passed. As early as 1803, to be sure, Berthollet in his famous 



