476 GEOLOGY OF NORTHWESTERN TEXAS. 



1. Potassium oxide 0.20 



2. Sodium oxide 0.40 



3. Calcium oxide, or lime 5.90 



4. Magnesium oxide, or magnesia 0.85 



5. Iron oxide 6.10 



6. Aluminum oxide 5.T0 



1. Manganese oxide 0.10 



8. Silicon oxide (sand) 64.80 



9. Sulphuric acid (anhydride) 0.20 



10. Phosphoric acid 0.45 



11. Carbonic acid 4.00 



12. Chlorine 0.20 



13. Organic matter 1.40 



100.00 

 SOILS OF THE PERMIAN. 



To apply the principles to the soils of the district embraced in the Permian 

 territory a brief description of the different classes of soils found therein will 

 be necessary. 



"There are three principal kinds of soils in this district, classed by their 

 derivation rather than by their chemical properties. The first are those de- 

 rived from the immediate underlying strata, and have only such foreign in- 

 gredients as have come from the decomposition of the vegetation growing 

 upon them from year to year. 



Soils of the first class are purely local and do not extend over very wide 

 areas in any one locality. They vary in composition and color according to 

 locality. Where they are derived from the massive friable sandstones and 

 clays they are quite sandy and have a deep red color. In such localities the 

 color and composition have been very little changed by vegetable deposits. In 

 the limestone belts, where the origin of the soil is due to the decomposition of 

 the limestones and the accompanying bluish clay beds, the soils are dark, and 

 in places are quite black. They have a good deal of vegetable material in 

 their composition, and owe their dark color largely to this fact. All of this 

 class of soils are more or less sandy. These 1 will call residual. They are 

 found along the north side of the Concho River, below San Angelo; in Tay- 

 lor County, near Abilene; in parts of Baylor and Wichita counties, as well 

 as all the counties in the Permian district. 



This class of soils is as good as any to be had in the district. All of them 

 can be improved by deep plowing, the deep plowing enabling the soils to 

 receive and retain the rain that may fall and store it up for future use of the 

 plants. These soils have been given practical tests, and have in every in- 

 stance given satisfaction where the tests have been fairly made. No more 

 prosperous farmers can be found in the State than those who are cultivating 



