abstracts: chemistry • 319 



from one soil or another. From the data obtained it would appear that 

 pentosans, pentose sugars, histidine, cytosine, xanthine, hypoxanthine 

 and dihydroxystearic acid are rather common soil constituents and are 

 likely to be encountered in soils everywhere. Although agroceric acid, 

 lignoceric acid, parafhnic acid, a-monohydroxystearic acid, as well as 

 agrosterol, phytosterol, and hentriacontane were only found in one or 

 two soils, no general statement covering their frequency or infrequency 

 of occurrence is warranted. Arginine, a common cleavage product of 

 protein, was found in only two soils and it is probably a soil constitu- 

 ent which persists in the soil only a short time. E. C. L. 



AGRICULTURAL CHEMISTRY.— Studies in organic soil nitrogen. 



E. C. Lathrop and B. E. Brown. Journal Industrial Engineering 



Chemistry, 3: 657-660. 1911. 

 The largest part of the N in the soil exists in complex organic forms, 

 and this paper deals with an analytical attempt to determine in what 

 combination this N exists. Five soils, Hagerstown loam, from the plats 

 of the Pennsylvania State College Experiment Station, which had been 

 under treatment since 1881 were examined. The soil was heated with 

 HC1 and in the acid solution total N, Ammonia N, mono and diamino 

 acid N and "Humin" N were determined by the method of Hausmann as 

 modified by Osborne and Harris. The NH 3 liberated and the amount 

 of soluble organic nitrogenous compounds caused by heating the soil 

 with water under pressure from 1 to 10 atmospheres was also studied. 

 By the latter method it was shown that the organic N in the lime- 

 treated plats was in different combination from that of the other plats. 

 There was a wide variation in the amounts of mono and diamino acid 

 N and there seemed to be no agreement between amino N and plat 

 treatment. The ammonia and amino acid Nwill be directly available for 

 plant use and, in these plats, these two together, form 40-60 per cent of 

 the total N in the soils. The " Humin" N is not considered to be directly 

 available and these soils would yield on decomposition 40-60 per cent 

 of such compounds. Since these 5 soils are. really the same soil under 

 long continued treatment of different kinds, the work shows that differ- 

 ent decomposition of the nitrogenous matter has taken place and prob- 

 ably will continue to take place under such different conditions imposed 

 in the field. E. C. L. 



