GREENE COUNTY. 109 
made. The clay for the wet-mud bricks is tempered and molded by 
steam, dried in covered racks, and burned in updraft clamp kilns. 
It requires about seven days for drying and fourteen days for burning. 
Wood is used for fuel. 
Two kinds of clay are present in the pit. The upper, porous 
yellow stratum is best adapted for making brick. The lower stratum 
is a compact, plastic gray clay which can not be used for brick with- 
out being mixed with the overlying yellow clay. When used alone 
it checks badly in drying. The wet-mud machine has a capacity of 
20,000 bricks a day. 
The clay for the dry press is stored in a dry shed for several weeks 
and is then molded into bricks and set in an updraft kiln. It requires 
about seventeen days to burn the dry-press bricks. The machine 
has a capacity of 15,000 bricks a day. About 50 per cent of the 
bricks made at Paragould are sold at the kiln; the remainder are 
shipped to neighboring towns. 
The following analysis was made from the reworked product of the 
loess at Paragould : 
Analysis of brick earth from the surface at Paragould. 
[Dried at 110°-115° C. Brackett & Smith, analysts.] 
Silica (Si0 2 ) 79. 07 
Alumina (A1 2 3 ) 8. 79 
Iron (Fe 2 3 ) 2. 54 
Lime (CaO) 1 
Magnesia (MgO) . . >(by difference) 2. 37 
Alkalies J 
Manganese (MnO) 3. 68 
Loss on ignition 3. 55 
100. 00 
Air-dried sand in air-dried clay 43. 64 
The percentage of iron found in analyses of Greene County clays 
is commonly sufficient to give the bricks a deep shade of red. In 
analyses of clay from Paragould only a trace of manganese appears. 
The red color of bricks made from loess clays, therefore, seems to be 
due to the iron alone. To get brown colors it will be necessary to 
add manganese-bearing clay. Lime and other alkalies form an 
inconsiderable portion of the whole clay. From these loess soils the 
best quality of pressed brick may be made. This has already been 
practically demonstrated at many places along the upper Mississippi 
River. 
