THE NITROGEN" OP PROCESSED FERTILIZERS. 



19 



isolation methods are as follows : The process by which the nitrogen 

 of certain trade wastes, such as hair, leather, garbage, etc., is made 

 more available, is recognized as a process of partial hydrolysis of the 

 complex protein contained in such materials, resulting in ammonia, 

 amino acids, etc., all of which are more available than the original 

 protein material. This hydrolysis is almost complete, the nitrogenous 

 compounds formed being principally the primary products of protein 

 hydrolysis, together with a small amount of proteoselike compound 

 which has not been fully decomposed. 



Table VI. — Products cf acid hydrolysis of various proteins. 



Compound. 



"Synotin" 

 from 

 cattle 

 flesh.i 



"Keratin" 



from 



sheep's 



liorn. 2 



"Keratin" 



from 



sheen's 



wool. 3 



"Keratin" 



from 



horse's 



hair. 4 



Halibut 

 muscle. 6 



Ox 

 muscle. 6 



"Legu- 



rnin" from 



pea.? 





0.5 



4.0 



.9 



7.8 



0.5 

 1.6 



4.5 

 15.3 



0.6 

 4.4 

 2.8 

 11.5 



4.7 

 1.5 

 .9 

 7.1 



0.0 



(?) 

 .8 

 10.4 



2.1 



3.7 



.8 



11.7 



4 





2.1 



Valine 





80 



Isoleucine 







2.5 

 2.2 



1.9 

 3.6 

 1.1 



7.5 

 3.7 





.0 

 3.2 



.6 

 8.0 

 3.4 



3.1 

 2.4 



(?) 



3.2 

 2.2 



(?) 



3 8 



Tyrosine 8 



2.9 



.1 

 7.3 



4.4 



1 6 



Serine 



.5 









Proline 



3.3 



3.2 



5.8 



3 2 







Aspartic acid s 



Glutamic acid s 



.0 



13.6 



2.5 



17.2 



2.3 

 12.9 



.3 

 3.7 



2.8 

 10.1 



( + ) 

 6.4 

 7.5 

 2.6 

 1.4 



4.52 

 15.5 



(+) 



7.5 

 7.6 

 1.8 

 1.1 



5.3 

 17.0 

 (+) 

 11.7 





5.1 



3.3 



2.7 



.9 



2.7 

 .2 





4.5 

 1.1 

 .6 







5.0 







1.7 









2.1 













Total 



47.3 



62.3 



49.2 



39.6 



50.7 



67.5 



62.4 







i E. Abderhalden and T. Saski, Zeit. physiol. Chem., 51, 404 (1907). 

 is *, e. Abderhalden and A. Voitinovici, ibid., 52, 348 (1907). 



« E. Abderhalden and H. G. Wells, ibid., 46, 31 (1905); A. Argiris, ibid., 54, 86 (1905). 

 6 T. B. Osborne and F. W. Heyl, Anier. J. Physiol., 22, 433 (1908). 

 «T. B. Osborne and D. B. Jones, ibid., 24, 437 (1909). 

 ' T. B. Osborne and F. W. Heyl, J. Biol. Chem., 5, 197 (1908). 



8 Physiological action on plant growth has been determined and reported in Bui. 87, Bureau of Soils. 

 U. S. Dept. Agr. 



AVAILABILITY OF THE NITROGEN OF ORGANIC FERTILIZERS. 



The question of the availability of the different kind of nitrogen 

 contained in organic fertilizers is one that has caused considerable 

 discussion. A number of methods have been proposed for determining 

 this factor, and while some of them give helpful results, all excepting 

 the plant method are open to more or less objection. The reason for 

 this is that the methods are empirical and the nature of the compli- 

 cated compounds in which the nitrogen is linked in the fertilizer is 

 unknown or only guessed. When these nitrogen compounds are 

 known and their action on plants as well as the action of the com- 

 pounds which will be formed from them during their decompo- 

 sition in the soil, has been determined, then the question of the 

 availability of the nitrogen of organic fertilizers can be understood. 

 Originally it was held that plants were only able to use nitrogen when 



