390 E. P. Deatrick 
TABLE 11. Oxmpation 1n Dunxrrk Sitt Loam TREATED wiTH MANGANESE SALTS 
(Tests made seven months after treatment) 
Parts per million of manganese added 
Relative oxidation 
Phenolphthalin 
(DME Melee tad alnee Ors mame RP aioe Bales oe Aaah alee Raia ea 100 100 
Potassium permanganate 
TO eerie bs enn Mee Oran cet mes alg cmt dO nee a cs OR os 101 100 
MO Festa eos veh ca ea Fira Ota av on aremrater Uh) Prete ary (eras pu taeee ne 136 120 
OOO § rd ee ee at tere aM adr 8 ip aan Reh Set Re 444 200 
Manganese dioxide 
COs eee see Batata ea Mn aren neat aM aN ce OL Ohne Dante ae 93 100 
LOO RA arte Lar ae CGN eit cme Peel pe Ody Aerie Rae Reel eeR Sree 94 100 
NOOO Reese o Aekan et tee aot a soe tS eRe he ects 95 100 
Manganese chloride 
LUO Yoers ee ea eG ERIS Ay Tp Ba Sn Coe aR rae CE NT 105 100 
ICO eee he Ste ee acs ate tartan x Paes cath Bice a een Re 113 125 
OOO ee aaa see pais (near, tebe Dicer ea hela ees 171 167 
‘ Manganese carbonate 
AL Sees SHE a pea cede car ene tata Aire Sarat i pal gaa eau e 105 100 
COLO egeeste oe eaeea eae NEMS eR FP ye tl ua (al te ien te Lod lie eS 117 100 
SIC) OO eh is Ae Tne IAIMR et De aa Sa ee ati ne ante et 128 142 
Manganese sulfate 
Ue Sen Ne lei rata 2 nit beac de cok pa eum pe acter ote 105 100 
OQ erate oe din ota ste avert Ter een tke STR garter ear 136 130 
TOTO a cre oe sc er CRON ede day SN eT TREO AC ays Merit 233 172 
Adsorption of manganese 
It had been noted that soil to which manganese salts were added devel- 
oped a power to oxidize aloin in proportion to the length of time that 
the salt was in contact with the soil. In order to test this more accurately, 
portions of soil, the moisture content of which had been held at 25 per 
cent for seven months, were treated with solutions of manganese sulfate. 
The data, given in table 12, indicate that oxidation does not develop at 
once, but that it is greatest in the soil in which the manganese has been 
present for the longest time. 
