INTRODUCTION 



THE work of Miss Helen C. De S. Abbott is prominent in 

 the annals of American chemistry. She was among the very 

 first investigators of this country who began in a systematic 

 way to study the relations of chemical composition to species 

 of plants and to plant growth. 



The work which she did is the more remarkable when it 

 is considered that it was mostly finished before the modern 

 science of physical chemistry was placed upon its present firm 

 foundation. In those days it was not acknowledged by all, 

 and was recognized by few, that chemistry was the basic sci- 

 ence of all forms of life. Investigators had not realized that 

 the so-called vital processes were nothing more nor less than 

 chemical reactions of greater or less complexity. With our 

 present understanding of the domain of physical chemistry, it 

 seems strange that the studies which Miss Abbott really inau- 

 gurated on this subject had not been begun at an earlier period. 

 This delay, however, detracts nothing from the credit due 

 her in being a pioneer in the work. 



The most important result of her investigations pointed 

 out in a clear way the regular existence of certain classes of 

 chemical bodies in certain species of plants. The results of 

 her investigations were to point out the existence as a predom- 

 inant factor of some one substance, or of associated compounds, 

 in classes of plants related by certain evolutionary common 

 features. The fact that occasional bodies of the same kind 

 are found in the most widely separated species and genera 

 is no indication of the futility of such an investigation. 



Miss Abbott studied particularly the occurrence and rela- 

 tion of glucosides in plants, and especially the remarkable 

 similarity in composition in certain plants related as above 

 mentioned. She established the fact l that the " Glucosides 



1 See paper on " Comparative Chemistry of Higher and Lower Plants." 



