22 GEOLOGY OF OHIO. 



other hand, scores of mounds of various sizes, in different localities, have 

 furnished proof that human toil alone was employed. In many, almost 

 the entire interior is composed of lenticular masses of earth, from a peck 

 to two pecks in volume, or as much as a man will easily carry, such as 

 could result only from loads of this size being flattened out by the weight 

 of the earth above them. They are not apparent in some mounds; sand 

 and certain kinds of clay or loam will often unite so that no division is 

 perceptible between different deposits; their regularity may have been 

 destroyed by the workmen passing over them; the earth scattered as it 

 was thrown down ; in shallow mounds or in the upper portion of large 

 ones their outlines may be effaced by the action of percolating water; but 

 as no indications of a different mode of construction have been reported, 

 from any source, it is fair to assume this was the ordinary method. 



A singular product of aboriginal notions, and one that seems peculiar 

 to Ohio mounds, is found in the so-called "altars." There are masses of 

 clay si* to eight feet across, — seldom larger — usually irregular in outline, 

 and up to a foot in thickness. A sufficient space of ground having been 

 cleared off and sometimes burned or pounded until hard, the material was 

 spread out, kneaded or "puddled" to a firm and uniform consistency, the 

 upper surface made smooth and flat, and a basin excavated in it. This 

 is always rectangular, with rounded corners and a level bottom. It varies 

 from three to five feet in length with a width one-half to three-fourths as 

 much, and a depth of four to eight inches; very few fall beyond these 

 Umits in either direction. The margin of the cla}^ was either left as it 

 had been deposited, or cut away its entire thickness to form a rim of 

 uniform width around the basin. A fire was then kept burning on it 

 until all the clay remaining was hard as a brick. Sometimes all the ashes 

 and charcoal resulting from the fire were carefully removed; in this case 

 the altar-cavity is usually filled with fine, dark earth, possibly resulting 

 from decayed organic substance, or with clean white ashes. Occasionally 

 it contains human bones which ma}' belong to adults or to children, may 

 be nearly consumed by heat or may show no trace of fire. The name 

 "altar" is derived from the deposits, presumably sacrificial offerings, 

 frequently found on them; though quite often they contain no relics. 

 Some yield only a pipe, a fine spear-head, ornaments, or a few other arti- 

 cles, generally well-finished. In others the contents amaze the most 

 experienced explorer. Ornamental objects of every material which it was 

 possible for a primitive people to obtain or utilize ; minerals whose near- 

 est beds are hundreds of miles away; shells from the ocean or gulf; 

 stamped and carved figures in copper whose design points unmistakably 

 to a Mexican origin; — all occur, some in the greatest profusion. From a 

 single altar near Madisonville were taken fully two bushels of specimens; 

 among them alligator and shark teeth curiously carved; thousands of 

 pearl beads, ornaments of copper, shell, bone, quartz, slate, meteoric iron, 

 and many other materials; besides objects whose use is not apparent. 



