WORKS OF DEFENCE.

Those works which are incontestibly defensive usually occupy strong natural positions; and to understand fully their character, their capability for defence, and the nature of their entrenchments, it is necessary to notice briefly the predominant features of the country in which they occur. The valley of the Mississippi river, from the Alleghanies to the ranges of the Rocky Mountains, is a vast sedimentary basin, and owes its general aspect to the powerful agency of water. Its rivers have worn their valleys deep into a vast original plain; leaving, in their gradual subsidence, broad terraces, which mark the eras of their history. The edges of the table-lands, bordering on the valleys, are cut by a thousand ravines, presenting bluff headlands and high hills with level summits, sometimes connected by narrow isthmuses with the original table, but occasionally entirely detached. The sides of these elevations are generally steep, and difficult of access; in some cases precipitous and absolutely inaccessible. The natural strength of such positions, and their susceptibility of defence, would certainly suggest them as the citadels of a people having hostile neighbors, or pressed by invaders. Accordingly we are not surprised at finding these heights occupied by strong and complicated works, the design of which is no less indicated by their position than by their construction. But in such cases, it is always to be observed, that they have been chosen with great care, and that they possess peculiar strength, and have a special adaptation for the purposes to which they were applied. They occupy the highest points of land, and are never commanded from neighboring positions. While rugged and steep on most sides, they have one or more points of comparatively easy approach, in the protection of which the utmost skill of the builders seems to have been exhausted. They are guarded by double, overlapping walls, or a series of them, having sometimes an accompanying mound, designed perhaps for a look-out, and corresponding to the barbican in the system of defence of the Britons of the middle era. The usual defence is a simple embankment, thrown up along and a little below the brow of the hill, varying in height and solidity, as the declivity is more or less steep and difficult of access.

Other defensive works occupy the peninsulas created by the rivers and large p010 streams, or cut off the headlands formed by their junction with each other. In such cases a fosse and wall are thrown across the isthmus, or diagonally from the bank of one stream to the bank of the other. In some, the wall is double, and extends along the bank of the stream some distance inwardly, as if designed to prevent an enemy from turning the flanks of the defence.

To understand clearly the nature of the works last mentioned, it should be remembered that the banks of the western rivers are always steep, and where these works are located, invariably high. The banks of the various terraces are also steep, and vary from ten to thirty and more feet in height. The rivers are constantly shifting their channels; and they frequently cut their way through all the intermediate up to the earliest-formed, or highest terrace, presenting bold banks, inaccessibly steep, and from sixty to one hundred feet high. At such points, from which the river has, in some instances, receded to the distance of half a mile or more, works of this description are oftenest found.

And it is a fact of much importance, and worthy of special note, that within the scope of a pretty extended observation, no work of any kind has been found occupying the first, or latest-formed terrace. This terrace alone, except at periods of extraordinary freshets, is subject to overflow.[8] The formation of each terrace constitutes a sort of semi-geological era in the history of the valley; and the fact that none of the ancient works occur upon the lowest or latest-formed of these, while they are found indiscriminately upon all the others, bears directly upon the question of their antiquity.

In addition to the several descriptions of defensive works above enumerated, there are others presenting peculiar features, which will be sufficiently noticed in the plans and explanations that follow. These plans are all drawn from actual and minute, and in most instances personal survey, and are presented, unless otherwise specially noted, on a uniform scale of five hundred feet to the inch. When there are interesting features too minute to be satisfactorily indicated on so small a scale, enlarged plans have been adopted. This is the case with the very first plan presented. Sections and supplementary plans are given, whenever it is supposed they may illustrate the description, or assist the comprehension of the reader. To shorten the text, the admeasurements are often placed upon the plans, and the “Field Books” of survey wholly omitted. The greatest care has, in all cases, been taken to secure perfect fidelity in all essential particulars. In the sectional maps, in order to show something of the character as well as the positions of the works, it has been found necessary to exaggerate them beyond their proportionate size. Some of the minor features of a few works are also slightly exaggerated, but in no case where it would be apt to lead to misapprehension or wrong conceptions of their character. p011

[♠] IV. Ancient Stone Work near the village of Bourneville, Ross Co. Ohio, 12 miles west of Chillicothe.

PLATE IV.[9] STONE WORK, NEAR BOURNEVILLE, ROSS COUNTY, OHIO.

This work occupies the summit of a lofty, detached hill, twelve miles westward from the city of Chillicothe, near the village of Bourneville. The hill is not far from four hundred feet in perpendicular height; and is remarkable, even among the steep hills of the West, for the general abruptness of its sides, which at some points are absolutely inaccessible. It is the advance point of a range of hills, situated between the narrow valleys of two small creeks; and projects midway into the broad valley of Paint creek, so as to constitute its most prominent natural feature. It is a conspicuous object from every point of view. Its summit is a wide and fertile plain, with occasional considerable depressions, some of which contain water during the entire year.

The defences consist of a wall of stone which is carried around the hill, a little below the brow; but at some places it rises, so as to cut off the narrow spurs, and extends across the neck that connects the hill with the range beyond. It should not be understood by the term wall, that, at this time, anything like a wall of stones regularly laid up exists; on the contrary, where the line is best preserved, there is little evidence that the stones were laid one upon the other so as to present vertical faces, much less that they were cemented in place. At a few points, however, more particularly at the isthmus D, there are some indications of arrangement in the stones, tending to the belief that the wall here may have been regularly faced on the exterior. The appearance of the line, for the most part, is just what might be expected from the falling outwards of a wall of stones placed, as this was, upon the declivity of a hill. Upon the western, or steepest face of the hill, the range of stones covers a space varying from thirty to fifty feet in width, closely resembling the “protection walls” carried along the embankments of rail-roads and canals, where exposed to the action of rivers or large streams. But for the amount of stones, it might be taken for a natural feature,—the debris of the out-cropping sand strata. Such, certainly, is the first impression which it produces upon the visitor; an impression, however, which is speedily corrected upon reaching the points where the supposed line of debris, rising upon the spurs, forms curved gateways, and then resumes its course as before.

Upon the eastern face of the hill, where the declivity is least abrupt, the wall is heavier and more distinct than upon the west, resembling a long stone-heap of fifteen or twenty feet base, and from three to four feet in height. Where it crosses the isthmus it is heaviest; and although stones enough have been removed from it, p012 at that point, to build a stout division wall between the lands of two proprietors, their removal is not discoverable. This isthmus is seven hundred feet wide, and the wall is carried in a right line across it, at its narrowest point. Here are three gateways opening upon the continuous terrace beyond. These are formed by the curving inward of the ends of the wall for forty or fifty feet, leaving narrow pass-ways between, not exceeding eight feet in width. At the other points, A and C of the plan, where there are jutting ridges, are similar gateways. It is at these points that the hill is most easy of access. At A is a modern roadway; at C is a pathway leading down into the valley of “Black Run.” At B appears to have been a similar gateway, which for some reason was closed up; a like feature may be observed in the line D. At the gateways, the amount of stones is more than quadruple the quantity at other points, constituting broad, mound-shaped heaps. They also exhibit the marks of intense heat, which has in some instances vitrified their surfaces, and fused them together. Light, porous scoriæ are abundant in the centres of some of these piles. Indeed, strong traces of fire are visible at many places on the line of the wall, particularly at F, the point commanding the broadest extent of country. Here are two or three small mounds of stone, which seem burned throughout. Nothing is more certain than that powerful fires have been maintained, for considerable periods, at numerous prominent points on the hill; for what purposes, unless as alarm signals, it is impossible to conjecture.[10]

It will be observed that the wall is interrupted for some distance at E, where the hill is precipitous and inaccessible. There are, as has already been remarked, several depressions upon the hill which contain constant supplies of water. One of them covers about two acres, and furnishes a supply estimated by the proprietor as adequate to the wants of a thousand head of cattle. Water is obtained in abundance at the depth of twenty feet.

The area enclosed within this singular work is something over one hundred and forty acres, and the line of the wall measures upwards of two and a quarter miles in length. Most of the wall, and a large portion of the area, are still covered with a heavy primitive forest. Trees of the largest size grow on the line, twisting their roots among the stones, some of which are firmly imbedded in their trunks.

That this work was designed for defence, will hardly admit of doubt; the fact is sufficiently established, not less by the natural strength of the position, than by the character of the defences. Of the original construction of the wall, now so completely in ruins, we can of course form no very clear conception. It is possible that it was once regularly laid up; but it seems that, if such were ever the case, some satisfactory evidence of the fact would still be discoverable. We must consider, however, that it is situated upon a yielding and disintegrating declivity; and that successive forests, in their growth and prostration, aided by the action of the elements, in the long period which must certainly have elapsed since its p013 construction, would have been adequate to the total demolition of structures more solid and enduring than we are justified in supposing any of the stone works of the ancient people to have been. The stones are of all sizes, and sufficiently abundant to have originally formed walls eight feet high, by perhaps an equal base. At some points, substantial fence-lines have been built from them, without sensibly diminishing their numbers. It can readily be perceived that, upon a steep declivity, such as this hill presents, so large an amount of stones, even though simply heaped together, must have proved an almost insurmountable impediment in the way of an assailant, especially if they were crowned by palisades.

In the magnitude of the area enclosed, this work exceeds any hill-work now known in the country; although the wall is considerably less in length than that of “Fort Ancient,” on the Little Miami river. It evinces great labor, and bears the impress of a numerous people. The valley in which it is situated was a favorite one with the race of the mounds; and the hill overlooks a number of extensive groups of ancient works, the bearings of which are indicated by arrows on the plan.

Paint creek washes the base of the hill upon the left, and has for some distance worn away the argillaceous slate rock, so as to leave a mural front of from fifty to seventy-five feet in height. It has also uncovered a range of septaria, occurring near the base of the slate stratum; a number of which, of large size, are to be seen in the bed of the creek, at a. These, most unaccountably, have been mistaken for works of art,—“stone covers” for deep wells sunk in the rock. This notion has been gravely advanced in print; and the humble septaria, promoted to a high standing amongst the antiquities of America, now figure prominently in every work of speculations on the subject. The reason for sinking wells in the bed of a creek, was probably never very obvious to any mind. The supposed “wells” are simple casts of huge septaria, which have been dislodged from their beds; the cyclopean “covers” are septaria which have resisted the disintegrating action of the water, and still retain their places. Parallel ranges of these singular natural productions run through the slate strata of this region: they are of an oblate-spheroidal figure, some of them measuring from nine to twelve feet in circumference. They frequently have apertures or hollows in their middle, with radiating fissures, filled with crystalline spar or sulphate of baryta. These fissures sometimes extend beyond them, in the slate rock, constituting the “good joints” mentioned by some writers. The slate layers are not interrupted by these productions, but are bent or wrapped around them. The following cut illustrates their character. A is a vertical section: a exhibiting the water, b the rock. At c the septarium has disintegrated, or has been removed, and its cavity or bed is filled with pebbles. At d the nodule still remains. B exhibits the appearance presented by d from above.

Fig. 2.

A stone work, somewhat similar in character to that here described, exists near the town of Somerset, Perry county, Ohio. It is described by Mr. Atwater in the Archæologia Americana, vol. i. p. 131. p014

Still another, of small size and irregular outline, is situated on Beaver creek, a branch of the Great Kenhawa, in Fayette county, Virginia, of which an account was published by Mr. I. Craig of Pittsburgh, in the “American Pioneer,” vol. i. p. 199.

PLATE V. “FORT HILL,” HIGHLAND COUNTY, OHIO.[11]

This work occurs in the southern part of Highland county, Ohio; and is distant about thirty miles from Chillicothe, and twelve from Hillsborough. It is universally known as “Fort Hill,” though no better entitled to the name than many others of similar character. The defences occupy the summit of a hill, which is elevated five hundred feet above the bed of Brush creek at its base, and eight hundred feet above the Ohio river at Cincinnati. Unlike the hills around it, this one stands detached and isolated, and forms a conspicuous object from every approach. Its sides are steep and precipitous; and, except at one or two points, if not absolutely inaccessible, extremely difficult of ascent. The points most easy of access are at the southern and northern angles, and may be reached on horseback. The top of the hill is level, and has an area of not far from fifty acres, which is covered with a heavy primitive forest of gigantic trees. One of these, a chestnut, standing on the embankment near the point indicated by the letter e, measures twenty-one feet in circumference; another, an oak, which also stood on the wall, at the point f, though now fallen and much decayed, still measures twenty-three feet in circumference. All around are scattered the trunks of immense trees, in every stage of decay; the entire forest presenting an appearance of the highest antiquity.

[♠] V. Fort Hill, Highland Co. Ohio.

Thus much for its natural features. Running along the edge of the hill is an embankment of mingled earth and stone, interrupted at intervals by gateways. Interior to this is a ditch, from which the material composing the wall was taken. The length of the wall is eight thousand two hundred and twenty-four feet, or something over a mile and a half. In height, measuring from the bottom of the ditch, it varies from six to ten feet, though at some places it rises to the height of fifteen feet. Its average base is thirty-five or forty feet. It is thrown up somewhat below the brow of the hill, the level of the terrace being generally about even with the top of the wall; but in some places it rises considerably above, as shown in the sections. The outer slope of the wall is more abrupt than that of the hill; the earth and stones from the ditch, sliding down fifty or a hundred feet, have formed a p015 declivity for that distance, so steep as to be difficult of ascent, even with the aid which the trees and bushes afford. The ditch has an average width of not far from fifty feet; and, in many places, is dug through the sandstone layer upon which the soil of the terrace rests.[12] At the point A, the rock is quarried out, leaving a mural front about twenty feet high. The inner declivity of the ditch appears to have been terraced. It descends abruptly from the level for a few feet, then declines gently for some distance, and again dips suddenly, as it approaches the wall. The vertical section a b exhibits this feature.

There are thirty-three gateways or openings in the wall, most of them very narrow, not exceeding fifteen or twenty feet in width at the top: only eleven of these have corresponding causeways across the ditch. They occur at irregular intervals; and some of them appear to have been rather designed to let off the water which might otherwise accumulate in the ditch, than to serve as places of egress or ingress. Indeed, most of them cannot be supposed to have been used for the last named purposes, inasmuch as they occur upon the very steepest points of the hill, and where approach is almost impossible. At the northern and southern spurs or angles of the hill, the gateways are widest, and the parapet curves slightly outwards. The ditch is interrupted at these points.

There are three depressions or ponds within the enclosure; the largest of these, g, has a well-defined artificial embankment on its lower side, which has recently been cut through, and the water principally drawn off. When full, the water must have covered very nearly an acre. Bog-clumps are growing around its edges, and it is free from trees. It does not seem to have any perennial sources of supply. There are several other small circular depressions, a number of which occur together at the bluff A; there are also traces of other excavations, not clearly defined, at various points on the hill.

An inspection of the plan of the work, shows that it is naturally divided into three parts; that at A being, in many respects, the most remarkable. It is connected with the main body of the work by a narrow ridge but one hundred feet wide, and terminates at a bold, bluff ledge, the top of which is thirty feet above the bottom of the trench, and twenty feet above the wall. This bluff is two hundred feet wide. It is altogether the most prominent point of the hill, and commands a wide extent of country. Here are strong traces of the action of fire on the rocks and stones; though whether remote or recent, it is not easy to determine. The connection between the two principal divisions of the work is also narrow, being barely two hundred and fifty feet in width.

Such are the more striking features of this interesting work. Considered in a military point of view, as a work of defence, it is well chosen, well guarded, and, with an adequate force, impregnable to any mode of attack practised by a rude, or semi-civilized people. As a natural stronghold, it has few equals; and the p016 degree of skill displayed and the amount of labor expended in constructing its artificial defences, challenge our admiration, and excite our surprise. With all the facilities and numerous mechanical appliances of the present day, the construction of a work of this magnitude would be no insignificant undertaking. And when we reflect how comparatively rude, at the best, must have been the means at the command of the people who raised this monument, we are prepared to estimate the value which they placed upon the objects sought in its erection, and also to form some conclusion respecting the number and character of the people themselves.

It is quite unnecessary to recapitulate the features which give to this the character of a military work; for they are too obvious to escape attention. The angles of the hill form natural bastions, enfilading the wall. The position of the wall, the structure of the ditch, the peculiarities of the gateways where ascent is practicable, the greater height of the wall where the declivity of the hill is least abrupt, the reservoirs of water, the look-out or citadel, all go to sustain the conclusion.

The evidence of antiquity afforded by the aspect of the forest, is worthy of more than a passing notice. Actual examination showed the existence of not far from two hundred annual rings or layers to the foot, in the large chestnut-tree already mentioned, now standing upon the entrenchments. This would give nearly six hundred years as the age of the tree. If to this we add the probable period intervening from the time of the building of the work to its abandonment, and the subsequent period up to its invasion by the forest, we are led irresistibly to the conclusion, that it has an antiquity of at least one thousand years.[13] But when we notice, all around us, the crumbling trunks of trees half hidden in the accumulating soil, we are induced to fix upon an antiquity still more remote.

It is worthy of note, that this work is in a broken country, with no other remains, except perhaps a few small, scattered mounds, in its vicinity. The nearest monuments of magnitude are in the Paint creek valley, sixteen miles distant, from which it is separated by elevated ridges. Lower down, on Brush creek, towards its junction with the Ohio, are some works; but none of importance occur within twelve miles in that direction.

[♠] VI. Fortified Hill, Butler Co. Ohio, 3 Mile S. W. of the town of Hamilton.