132 



SCIENCE 



[N. S. Vol. XXXIII. No. 83? 



similar to Woehler's followed, although 

 somewhat tardily. Kolbe in 1845 showed 

 that it was possible to synthesize acetic 

 acid from its elements. Berthelot in 1854 

 likewise built up the fats. In the light of 

 such achievements the most skeptical could 

 no longer maintain the old view concerning 

 the impossibility of building up in the lab- 

 oratory from inorganic sources those com- 

 pounds naturally occurring in the living 

 organism. The recognition of this great 

 truth opened up to chemists a new line of 

 investigation and from that time the syn- 

 thetic preparation of organic compounds 

 has ever been a fruitful field of research. 

 It has sometimes seemed to me, however, 

 that in the enthusiasm over the discoveries 

 which chemists have made in this field of 

 investigation we are inclined to over-esti- 

 mate the work done, great as that may be. 

 and perhaps unintentionally convey the 

 impression that the chemical changes ta- 

 king place in the living organism are 

 thoroughly understood and can be dupli- 

 cated in the laboratory. While of course 

 it is true that many of the compounds in 

 the living organism have been synthesized 

 and that the number of such syntheses is 

 constantly increasing, yet we must not for- 

 get that the chemist's method has never 

 been, in detail at least, the method of 

 nature. Indeed, as a rule they are widely 

 divergent. We are apt to employ power- 

 ful reagents many of which so far as is 

 known do not exist in the organism 

 nor in the mediums from which it draws its 

 sustenance. The drastic treatment to 

 which these substances are often subjected 

 and the temperatures at which the reac- 

 tions are carried on are all in the greatest 

 contrast to the conditions which prevail in 

 the organism in which the natural syn- 

 thesis is effected. In a few cases the labo- 

 ratory methods employed more nearly ap- 

 proach the conditions which prevail in 



nature and such syntheses always have a 

 greatly added interest at least from a the- 

 oretical standpoint. Thus the observation 

 of Loew* that a sugar-like compound could 

 be formed by the condensation of formalde- 

 hyde was exceedingly important, but this 

 importance was greatly enhanced by the 

 fact that this condensation could be ef- 

 fected by the action of mild alkalis or even 

 neutral substances at ordinary tempera- 

 tures — conditions which approximate those 

 existing in the growing plant. Likewise 

 the importance of the observations of 

 Lobry de Bruyn and van Ekenstein^ that 

 the three hexoses, namely, mannose, fruc- 

 tose and dextrose, are mutually convert- 

 ible, lay largely in the fact that these 

 transformations could be made to take 

 place at ordinary temperatures under the 

 influence of reagents that may exist in the 

 soil. The study of such problems as these 

 has become not only one of the most allur- 

 ing and fascinating in the fields of research 

 in organic chemistry, but their solution is 

 fraught with the greatest significance, 

 since it will be a step in the direction of 

 gaining some understanding of the myster- 

 ies of life itself. 



Inasmuch as the carbohydrates play 

 such an important part in the economy of 

 the vegetable kingdom, it is quite natural 

 that the investigations of the problems per- 

 taining to the synthesis of compounds in 

 the living organisms have been largely 

 directed towards this class of compounds. 

 Since it is impossible in a short time to 

 discuss with any thoroughness the various 

 researches carried out in this field of in- 

 vestigation I will confine myself to those 

 which have some important bearing upon 

 the weU-known hypothesis proposed by 

 Baeyer, with a view of determining, if pos- 



*J. prakt. Chem., 33, p. 321. 

 'Ber. d. chem. Gesell., 28, p. 3078. 



