PRE-HISrORIC YANKEES. 655 
are noteworthy for their size, some for the shapes which they assume. Among 
these the most remarkable are the serpent and turtle mounds of Ohio, and the 
elephant mound of Wisconsin. . The serpent mound is more properly an em- 
bankment, over seven hundred feet long, extending in sinuous curves along the 
summit of a ridge ; ending at one extremity in a triple coil, and at the other in 
the head and open jaws of a snake. Within the jaws is an oval mound of no 
insignificant proportions itself; and it has been thought by some archaeologists 
that the oriental symbol of a serpent swallowing an egg was intended by its 
builders. Its head, however, with the accompanying mound, is suggestive of the 
Egyptian tau, or cross, with its oval loop, as the neck of the snake is intersected 
just behind the head by a bar, which is certainly no natural complement of the 
animal. The mound referred to as representing the form of an elephant leaves a 
strong suggestion in the mind, that this mysterious people either knew familiarly 
the now extinct mastodon or else brought from some other land a memory of the 
elephant; especially as its testimony is supplemented by a pipe in the same shape 
from an Iowa mound. These so-called animal mounds are in fact immense bas- 
reliefs of men, beasts, birds and reptiles. Cruciform mounds are also found, 
some pointing with great exactness to the cardinal points. 
II. Embankments or ramparts. These may be distinguished as cither 
defensive or religious, though many possess no obvious significance. Those of 
a military character manifest a respectable progress in the art of war. In some 
instances the intrenchments surround extensive areas and, occasionally, they are 
carried— like the Chinese wall and Offa's Dyke in Great Britain— over long 
stretches of country and connect the monuments of widely separated communities. 
Usually, however, these works seem to have formed citadels of refuge, easy of 
access and secure from assault when the wild people of the woods took the war- 
path. Sometimes a precipitous hill was chosen as the nucleus of the fortress ; 
sometimes an ocean headland, or a peninsula whose steep and rocky sides pro- 
jected into a stream, was selected as a position to be easily fortified and defended ; 
sometimes contiguous streams were connected by canals and the strong position 
thus created further strengthened by embankments and stone walls. The ap- 
proaches to many of these fortifications are protected by defenses that show no 
mean ability in the practice of the miHtary art. In one case the approach to an 
aboriginal fort is along a covered road with embankments on each side thirty 
feet in height. Very frequently these defensive works are connected with re- 
mains of some or all of the other classes described; and they are the most widely 
distributed and the most homogeneous in character of all these remains. Indeed, 
plans drawn from earthworks in the Mississippi basin bear so strong a resem- 
blance to those in British Columbia and even to those left by the Pueblo or CHff 
Indians of the Rocky Mountains that they have served to delineate the features 
■of these works with very slight alterations. 
The enclosures presumed to be of a religious nature, are well calculated to 
arouse curiosity. They are usually combinations of geometrical figures, in which 
perfect squares and circles predominate. It is obvious from this fact that the 
