INOKGANIC COMPOSITION OF SOME AMEBICAN SOILS. 21 
No. 5 sand. — Minerals other than quartz, 4.5 per cent. Potash 
feldspars (orthoclase), 1 per cent. Muscovite, 2 per cent. Epidote 
and augite are the predominant minerals. Chlorite, zircon, silli- 
manite, biotite, hypersthene, magnetite, augite, plagicclases, and 
hornblende are also present. The angular quartz grains are nearly 
transparent, but the subangular and rounded grains inclose iron oxide. 
Silt. — Minerals other than quartz, 43 per cent. Potash feldspars 
(orthoclase), 2 per cent. Muscovite, 5 per cent. Chlorite very 
abundant. Biotite, sillimanite, zircon, epidote, hornblende, and 
feldspar residues are also present. 
(16) CECIL CLAY, SOIL. 
No. 4 sand. — Minerals other than quartz, 2 per cent. No potash 
feldspars. Muscovite, 1 per cent. Magnetite and biotite are also 
present. 
No. 5 sand. — Minerals other than quartz, 4 per cent. Potash 
feldspars (orthoclase), 1 per cent. Muscovite, 1 per cent. Mag- 
netite, biotite, hornblende, and feldspar residues are also present. 
Silt. — Minerals other than quartz, 60 per cent. Potash feldspar 
(orthoclase), 3 per cent. Muscovite, 2 per cent. Feldspar resi- 
dues and chlorite abundant. Epidote, zircon, magnetite, hematite, 
biotite, and plagioclases are present. 
(17) CECIL SANDY LOAM, SOIL. 
No. 4- sand. — Minerals other than quartz, 7 per cent. Potash 
feldspars (orthoclase), 1.5 per cent. No muscovite. Magnetite, 
rutile, inclosed in quartz, indeterminable plagioclase, and hornblende 
are also present. 
No. 5 sand. — Minerals other than quartz, 8.3 per cent. Potash 
feldspars (microcline and orthoclase), 3.6 per cent. Microcline, 
orthoclase, and zircon are most abundant. Hornblende, muscovite, 
magnetite, chlorite, and apatite inclusions in quartz are present. 
Quartz grains are mostly clear, transparent, and angular to sub- 
angular. 
Silt. — Minerals other than quartz, 30 per cent. Potash feldspars, 
2 per cent. Muscovite, 2 per cent. Epidote, feldspar residues, 
zircon, chlorite, and magnetite are present. 
(18) CECIL SANDY LOAM, SUBSOIL. 
No. 5 sand. — Minerals other than quartz, 12 per cent. Potash 
feldspars (microcline and orthoclase), 3.6 per cent. Microcline, 
orthoclase, and zircon predominate. Hornblende, magnetite, chlorite, 
muscovite, biotite, epidote, plagioclase, and apatite inclusions in 
quartz are aJso present. The quartz consists of an equal number of 
clear transparent grains and those carrying inclusions or coatings 
of iron oxide. 
