396 EK. P. Deatrick 
mined by adding concentrated sodium hydroxide, distilling, and titrating 
the distillate with tenth-normal hydrochloric acid. The nitrates were 
determined by the phenol-disulfonic-acid method, using the Schreiner 
colorimeter to read the intensity of color. 
Ammonification.— To the soil used for ammonification tests was first 
added 0.5 per cent of dried blood. The manganese sulfate was added 
after the soil had been weighed out and placed in the culture bottles. 
Sufficient water was used as the solvent of the manganese sulfate to bring 
the soil in each culture to a moisture content of 25 per cent (dry basis). 
The cultures were incubated for one week, at the end of which extracts 
and determinations were made as described above. The results are given 
in tables 15 and 16: 
TABLE 15. Errect oF MANGANESE SULFATE ON AMMONIFICATION OF DRIED BLoop IN 
DUNKIRK Sitt Loam 
(Cultures incubated for seven days) 
Nitrogen 
Me as ammonia, Relmties 
Parts per million of manganese added average of t 
4 cultures Be 
(milligrams) 
(OS Ssh eae lected cae nee eit rears ean oan eet ltl ote os ad 34 100 
Oa ieee ead aun ene GEA A NOs OR REG eet Nc A ARMM a mae ene Oc 47 138 
DAU tsa ects Sisk Pes em terran ccc pn CR eee nat agate nee Sot ee vbr Bede ee le oh: 53 156 
CaO eather Sa rs Seen tiae Sept oedir Pom RNA eS Oo eat ere eee isl a 47 138 
SOR ae Rea Sgt a eee PS A Lt: cee SRN e.g ree Aca eee 54 159 
TUseieyed eka aes SON ens Ree a SUG os oop e oma tM tect 58 170 
TOO een res ade oe aie. ee edn co ein SiN a MLE areas ahasea 67 197 
TABLE 16. Errect or MANGANESE SULFATE AND 20,000 Parts per Minion or CaLcrum 
CARBONATE ON AMMONIFICATION OF DRIED BLoop In DUNKIRK Sr~ttT Loam 
(Cultures incubated for seven days) 
Nitrogen 
P lla i dded aac at’ | Relative 
arts per ion of manganese adde average 0 
4 cultures SHOUntS 
(milligrams) 
ek RECS OS To Ca aN aoc piled UN ie EN a 87 100 
(OO eee Peak eerie ate teiia: | San Malis ae Stat Perey FAS ates Sule ae 96 110 
TODO eA Ree as aed Seep Om oh gs oat has eT ae a a 109 125 
