26 Ancient Remains, Animal Mounds, $*c. in Wisconsin. 



to their present level, the angles and terminations are quite visi- 

 ble ; near the northwest angle of the citadel, however, part of 

 the embankment seems to have been destroyed, although it can 

 be traced some distance toward the head of the animal, repre- 

 sented as enclosing the northern side of the citadel. 



Fig. 2 is a section of the mound above referred to, showing 

 the manner in which it was examined, as well as the connection 

 of the superincumbent stratum of sod, with that of the original 

 upon which the mound is based. In the examination of this 

 mound, as well as in the measurement of some of the embank- 

 ments bounding the north side of the citadel, I am indebted to 

 the kindly assistance of James T. Hodge, Esq. of Plymouth, 

 Mass., a gentleman favorably known as having been a member 

 of the geological corps of the states of Maine and Pennsylvania. 

 Mr. H. also visited with me many of the figures noticed in this 

 article. In order effectually to examine the construction of this 

 mound, a shaft, about midway between top and bottom, of suffi- 

 cient dimensions to remove the earth conveniently, was sunk ; in 

 sinking to the depth of eight feet, we reached the original sod, 

 which here assumes a different character from that coating the 

 mound and the adjacent surface, being a hard and compact sub- 

 stance, denominated "hard-pan," caused, no doubt, from the pres- 

 sure of the immense weight of earth upon it for centuries. The 

 superincumbent mass, being a bed of ferruginous sand, having no 

 appearance of stratification, and being free from admixture, the 

 presumption is, that this mound was not constructed, as suggested, 

 by small contributions, but was heaped up in the progress of con- 

 struction to its completion without intermission. Continuing the 

 shaft through the original sod, (which measures here six inches in 

 thickness,) three feet farther, we found the substratum to be com- 

 posed of alternating layers of ferruginous earth and sand. Having 

 now sunk the shaft eleven feet from the surface, to remove the 

 earth without a windlass became too laborious; we then, com- 

 mencing above the hard-pan, penetrated the mound westwardly 

 fourteen feet, being some distance beyond the centre, conveying 

 the excavated earth through the shaft to the surface. Directly 

 under the centre of the mound, in the drift, we sunk another 

 shaft five feet in depth ; the substratum here compares with that 

 in the first shaft. Having now found much difficulty in remov- 

 ing the excavated earth, our drift being partially filled, we con- 



