November 1, 1912] 



SCIENCE 



579 



is again emphasized by what the other 

 speakers have told you. The problem is 

 not solved, though much progress has been 

 made through the application of modern 

 science. If the problem of soil fertility 

 had been solved by the application of such 

 statistics this symposium would not have 

 Been held. The pessimistic views expressed 

 I can not share. Science is ever optimistic ; 

 the scientific investigator must above all 

 things be optimistic and have an abiding 

 faith that science will solve the intricate 

 questions connected with his problem. The 

 problem of soil fertility and infertility is 

 broad enough and big enough for many 

 workers and methods of attack. We can 

 not all begin to unravel the tangled threads 

 at the same point ; there are different view- 

 points and it is not improbable that some 

 may have a keener vision than others to see 

 the particular thread that will undo the 

 snarl. The solution of the problem can 

 only be reached through results of diligent 

 experimentation, not by the statistics of 

 even a hundred years. Criticism of the 

 Bureau of Soils, similar to the present one, 

 have recurred frequently in the past few 

 years, as you are aware; but nevertheless 

 the Bureau of Soils has continued its work 

 from the new viewpoint and achieved some 

 important results which throw much light 

 upon the dark subject of the cause of fer- 

 tility and infertility of our agricultural 

 lands. I am very glad of this opportunity 

 to present to you the results of a phase of 

 this investigation, namely, the importance 

 of the organic constituents of soils. 



I have brought with me a tangible result 

 ©f this work in the form of specimens of 

 the organic compounds which have been 

 found in soils. Their isolation and iden- 

 tification give definite information about 

 a portion, and a very important portion, 

 •f the soil, the value of which has been 

 recognized in practise, but about which no 



definite information was at hand, until this 

 work was undertaken. By the application 

 of modem methods of research to the in- 

 tricate problems of the soil we have been 

 able to throw such light upon the biochem- 

 ical changes in soils that the old views of 

 soil organic matter, soil humus and the 

 process of humification are entirely over- 

 thrown. The compounds of which Mulder, 

 the contemporary of Liebig, writes, such as 

 humic acid, geic acid, ulmic acid, etc., 

 terms which have appeared in text-books 

 ever since, have absolutely no existence, 

 but are shown to be mixtures of many dif- 

 ferent, and widely different, compounds. 

 Not only were the compounds contained in 

 these specimen tubes not known as soil 

 constituents to Mulder or Liebig, but they 

 were unknown to science at that time. 

 With the advance of science since that 

 time, especially of biochemistry, results 

 such as these have been made possible. 

 Some of these compounds contain only car- 

 bon and hydrogen ; some, carbon, hydrogen 

 and oxygen; some, carbon, hydrogen, oxy- 

 gen and nitrogen; and some, carbon, hy- 

 drogen, oxygen, nitrogen and phosphorus. 

 The compounds represent a great variety 

 of chemical classes; there are paraffin hy- 

 drocarbons, hydroxyfatty acids and other 

 organic acids, esters and alcohols, carbo- 

 hydrates, hexone bases, pyrimidine deriva- 

 tives, purine bases and pyridine deriva- 

 tives. The individual compounds isolated 

 or found are as follows: 



ORGANIC COMPOUNDS ISOLATED AND IDENTiriED 



Hentriaeontane, Phytosterol, 



Paraffinie acid. Liquid glycerides, 



Lignocerie acid, Pieoline carboxylic acid, 



AgToeerie acid. Nucleic acid, 



Monohydrosystearic acid, Cytosine, 



Dihydroxystearie acid. Xanthine, 



Eesin, Hypoxanthine, 



Eesin acids. Adenine, 



Eesin esters, Histidine, 



Pentosan, Arginine, 



