Note 7 — Chapter I · - ETHNICAL PERIODS.
Reading edition
Geological Survey of Indiana, 1873, p. 119. He gives the following analysis: Ancient Pottery, “Bone Bank,” Posey Co., Indiana.
Moisture at 212° F.,1.00
Silica,36.00
Carbonate of Lime,25.50
Carbonate of Magnesia,3.02
Alumina,5.00
Peroxide of Iron,5.50
Sulphuric Acid,.20
Organic Matter (alkalies and loss),23.60
———
100.00