A mile to the north-west of the part of the work just described are the Octagon and works in connection with it. The Octagon is not quite regular, but the sides are very nearly equal. At each angle is a gateway, interior and opposite to which is a mound, as if to guard the opening. The cut gives a view of the Octagon, looking in through one of these gateways. At present, however, but a small portion is in the forest. Most of it is under cultivation, but the work can still be easily traced, and is one of the best preserved in the State. A portion of it, still in the forest, presents the same appearance to-day as it did to the first explorer. When a stranger for the first time wanders along the embankment and ascends the mounds, he can not fail to experience sensations akin to those of the traveler when he comes upon the ruins of some Old World city. We wish that for a brief space of time the curtain of the past would up-roll, and let us view these works while yet their builders flourished here. Gateway of Octagon. Connected with the Octagon by parallel walls three hundred feet long and placed sixty feet apart, is the smaller circle, “F.” This is a true circle, and is upwards of half a mile in circumference. A portion of it lying in the woods, still retains its primitive form, but the larger part is now under cultivation. There is no difficulty, however, in tracing its entire length. The most interesting feature in connection with this part of the work is immediately opposite the point of entrance from the octagon, and is represented in our next cut. At this point it seems as if the builders had started to make parallel walls, but afterwards changed their design and threw across the opening a large mound. From this mound a view of the entire embankment could be obtained. It is called the Observatory Mound. It has been so often dug into that it is now really in ruins, but is still too steep to be plowed over. Observatory Mound, Newark Works.