1922] WOODARD—SOIL FERTILITY 95 
soil samples are also quite similar in texture. Here again we find a 
high sulphur content with a high organic matter content, and a 
low sulphur content with a low organic matter content. When we 
compare different soil types or samples from the same type but 
from fields which have been cropped differently, however, there is 
little evidence of any relation. Samples 7 B and 9B have approxi- 
mately the same sulphur content, yet the volatile matter in the 
latter is twice that in the former. Both these samples are sub- 
soils from Ohio, and were taken from fields that were not far apart, 
but 7 B is on upland silt loam while 9 B is a muck soil. Again, the 
cropped soil (no. 15) and the virgin soil (no. 16) from Bentley’s 
farm, Indiana, differ only slightly in volatile matter, but differ 
widely in sulphur content. Gentry and Curry’s soil (no. 28) has 
slightly less volatile matter than Sharp’s soil (no. 30), but con- 
siderably more sulphur. Sample ro A from Wager’s farm in Wis- 
consin is a fine sandy loam soil with very little clay but a large 
amount of organic matter, as may be recognized by its black color, 
yet it contains considerably less sulphur than sample 2A from the 
Wah-Bee-Mee-Mee farm in Michigan, which is also a sandy loam 
soil, containing considerable coarse sand with sufficient organic 
matter to give a black color. 
It seems, then, that from the sulphur standpoint, as well as the » 
nitrogen standpoint, the character of the organic matter is of more 
importance than the amount. Sulphur, like nitrogen, is mainly 
present in the proteins, so that a small amount of high protein 
organic matter, such as one would obtain by plowing under leg- . 
umes, would be more valuable than a larger quantity of organic 
matter from wheat or oat straw or cornstalks. It seems probable 
also that the proteins are more readily decomposed than the non- 
protein organic matter, so that the sulphur and nitrogen would be 
oxidized more rapidly than the carbon, and the sulphur and nitrogen 
content might become quite low when there was still a consider- 
able amount of carbonaceous organic matter in the soil. 
In all the samples analyzed, the sulphur content was less than 
the phosphorus content. One of the samples from Ohio which 
was taken in a low wet place was a muck, very high in organic 
matter. This soil had nearly as much sulphur as phosphorus in 
