372 THE CHEMICAL PROBLEMS OF TO-DAY. 



tioiis, have been led into serious errors. The respect due to work of 

 the highest merit, continued for years, has thus been lessened. Ap- 

 parently this has even been overdone, and it is much to be deplored if 

 the interest of chemists for physical chemistry should be diminished 

 because some of its representatives are inclin«. d to over-rate the value 

 of their results. He who swims in the midst of high waves is unable 

 at times to see over the crests. 



Innumerable, also, are the problems which meet us in the domain of 

 organic chemistry. 



After the astonishing harvest of synthetical results which has been 

 reaped here, hardly any problem of synthesis seems unapproachable. 

 Since the artificial preparation of alizarin by Graebe and Liebermann, 

 of indigo by von Baeyer, of conine by Ladenburg, of uric acid by Hor- 

 baczewski and particularly by Behrend, since Emil Fischer and Kili- 

 ani have elucidated the chemistry of the sugar group and Wallach 

 that of the terpeues, we may well look hopefully for a clearer knowledge 

 of the bodies comprised under the name albumin, and to its synthesis. 



But even such success tends only to render us more modest, since 

 it shows us at the same time how narrow are the limits within which 

 chemical synthesis moves. Assuming even that the preparation of 

 albumin had been achieved, how infinitely far we should still be from 

 a conception of the nature of organised bodies ! Perhaps science is 

 separated by an impassable chasm from the artificial preparation of a 

 simple cell. Such an achievement lies at least beyond the sphere of 

 chemistry. 



But shall we reall^^ never succeed in sounding the process of assim- 

 ilation, which, in spite of its simplicity, presents itself to us so enig- 

 matically? Will it be found impossible to prepare artificially in our 

 laboratories, from carbon dioxide and water, sugar and starch, a proc- 

 ess which nature performs unceasingly in the green parts of plants ? 



The chemist however should not stej) prematurely upon the field of 

 biology while so many great j^roblems remain untouched in his own 

 I)eculiar sphere of investigation. 



The method of research in organic chemistry, in spite of the brilliant 

 successes already recorded, forces us even to-day to confess that only 

 a very minute proportion of known substances is within its reach. In 

 order to isolate an organic substance we are generally confined to the 

 purely accidental properties of crystallization or volatilization. Have 

 not those thousands of amorphous substances which cannot be char- 

 acterized by any chemical property and which the chemist is forced to 

 lay aside because he is unable either to purify them or to transform 

 them into volatile or crystallizable bodies, — have they not the same 

 claim upon our interest as their more beautiful and more manageable 

 comrades ? 



The most significant progress of organic chemistry does not consist 

 in single discoveries, nor in further expansion of synthetical success. 



