Shell mound

“ The objects of this material mentioned among the grave finds are supplemented by two implements, one of which came from the IInd, the other from the VIIIth stratum of the mound. Both are made of the haliotis shell, the material preferred for ornamental purposes by the Indians throughout the country. Recovered in different strata, they differ completely with respect to their form. Yet, owing to the scarcity of the finds we are not permitted to advance the opinion that the form of one was limited in its stratum to the complete exclusion of the other. ”

“ The mound is wholly artificial. It is conical and truncated, and of oval plan. Its summit measures, north and south, about 25 yards, and east and west about 40 yards, and its height is from 20 feet to 40 feet, according to the depth of its ditch, which is greatest on the northern side. The slopes are steep, the red earth having little disposition to slip.
The summit was crowned by a shell keep placed about 3 feet within the edge of the slope, and therefore about 23 yards north and south, by 38 yards east and west. ”

“ Fresh Water Shells. In all the mounds yet opened, examples of the Unio, or River Mussel, commonly known as the clam have been found. They are usually polished, cut into symmetrical shapes, and have holes bored in them. We have one which was no doubt used as a breast ornament, and was hung by a string around the neck. In the bottom of a nearly complete pottery cup, found in the grand mound, which went to pieces as we took it out, there was lying a polished clam shell. ”

“ The use made of the mound is to contain eggs, which are deposited in layers, and are then hatched by the heat generated in part from decomposition. The instant that the shell bursts, the young bird comes forth strong and large, and runs without the slightest care being taken of it by the parent. ”

“ It lays millions of eggs and hatches countless baby mollusks. It lives its life in its shell, lugging it around, snuggling into it when alarmed, burrowing into mud, fastening itself to a rock and creating ingenious camouflage. It builds its calcareous house with a great instinctive talent for color and sculpture. ”

“ If you examine the rocks which are left dry when the tide goes out, you will often find that they are covered almost all over with small shells which look rather like those of tiny limpets. Only at the top of each shell there is a little hole, from the margin of which a number of ridges run down to the bottom. And these ridges are so sharp, that if you happen to slip when you are wandering about among the pools, and catch at a rock to save yourself, they will cut your fingers almost as if they were knives. ”

“ MOLLUSCOUS SHELL DEPOSITS. The forms of marine life of importance in rock making thrive best in clear water, where little sediment is being laid, and where at the same time the depth is not so great as to deprive them of needed light, heat, and of sufficient oxygen absorbed by sea water from the air. In such clear and comparatively shallow water there often grow countless myriads of animals, such as mollusks and corals, whose shells and skeletons of carbonate of lime gradually accumulate in beds of limestone. ”

“ You find many with only the backs of their shells sticking out of the mud. This may be the creature’s natural position, but I find far more of them lying quietly on their sides in the shallow water, rocking gently to and fro in the placid undulations as if they were there but to show me their shining colors. But if you watch one intently for a time you will see him open his shell cautiously and put out one foot. ”

“ The situation of the base of the mound two feet below the water level cannot be explained on the assumption that refuse from a pile dwelling had been the first cause of its formation. This theory would presuppose modes of living to be followed by the Indians of this coast for which there is no parallel elsewhere, and which are not borne out by other evidence obtained in the study of the mound. If the mound has not risen from the water, then the former land surface must have sunk. ”

“ I have examined a small quantity of the dust taken from one of the shells found in the grand mound, with the microscope, and though I am not perfectly certain, yet I believe there are traces of some farinaceous substance to be seen. On skirting the shores of the Lake of the Woods into which Rainy River runs, at the present time, you are struck by the fact that there are no Canadian farmers there, and likewise that there are no mounds to be seen, while along the banks of Rainy River both the agriculturist is found cultivating the soil and the mounds abound. ”

“ The foot, on which it glides with a slow but smooth motion over the surface of the rock on which it habitually dwells, or, if you please, on the bottom of the saucer of sea-water in which you are examining it, is a broad expansion spreading out to twice the superficies of the base of the shell. Above this is the fleshy mantle, which is so turned up as closely to invest the shell, conforming to its shape, and even fitting into the grooves between the ridges. ”

“ Such are the prevailing characteristics of this class of mounds. It will be remarked that while all have the same general features, no two are alike in their details. They differ in the number and relative position of their sand strata, as well as in the size and shape of their altars and the character of the deposits made on them. One mound covers a deposit made up almost entirely of pipes, another a deposit of spear-heads, or of galena or calcined shells or bones. ”

“ One of the largest of their shells bursted within nine or ten yards of me: there was a single rock close by, about the size of a butt; and I got instant shelter under it in time to avoid the fury of the shell. Where it burst the earth was torn in such a manner that two or three butts might easily have gone into the hole it made, and it threw great quantities of stones and dirt to a considerable distance. ”

“ Now as the species in the early rocks differ from those found in later formations, quite as much as the latter from the mollusca of our modern seas, the gradual change in the character of the embedded shells marks a certain interval of time in the world’s history.” So we see that these rocks are the leaves of a great book, written all over with wonderful truths, and those who study such sciences as Geology and Conchology, are enabled to read much that is there written.
Every fossil shell that such a student picks out of the chalk, or limestone, is like a letter in the Alphabet of Creation ”

“ On the other hand, shells occurring in sheltered situations, estuaries, narrow straits, or even on open coasts where there is plenty of shelter from the waves, are comparatively of great size, with a well-developed, sometimes produced spire, and a mouth small in proportion to the area of shell surface. ”

“ Now these rocks are the bare bed of the shore, stripped of all covering. There is no mud, sand, or shingle, so here you see plainly the work done by the restless water. On every side you notice rocks worn to all shapes and sizes. Some jut out as sharp ledges. Others are flat tables, covered with a table-cloth of sea-plants. These clothe the rocks, or hang over the ledges like wet, shining green curtains. Nearly every rock has its crust of barnacles and clumps of mussels. If we are not careful we slip on the wet weeds, and get a ducking in the pools which lie everywhere among the rocks. ”

“ By such changes the water becomes once more clear and fit for the growth of stony zoophytes. Calcareous sand is then formed from comminuted shell and coral, or, in some cases, arenaceous matter replaces the clay; because it commonly happens that the finer sediment, being first drifted farthest from coasts, is subsequently overspread by coarse sand, after the sea has grown shallower, or when the land, increasing in extent, whether by upheaval or by sediment filling up parts of the sea, has approached nearer to the spots first occupied by fine mud. ”

“ So steep is the slope that sometimes they slip and roll a little way down it, but they always recover themselves and run up it again, none the worse. In the intervals between such little mishaps they seem to be picking minute shell-fish off the rock; but what shell-fish are they? for the small white ones, with which large areas of the rock are covered, are as hard as stone, and might defy anything short of a hammer and chisel to dislodge them. It is not on these assuredly that these soft little things are feeding, and now I see that where they are most active the rock is black. ”

“ We next notice that these shells are precisely similar to those still found with living occupants in the river below, only they are no longer of a brownish colour, but owing to the loss of the animal matter of the shell have an earthy, dirty-white appearance. To carry these home they should be packed in bran in one of your tins with a note as follows made on a piece of paper and placed just inside—"Sand in gravel: topmost bed —— pit, August 2nd, 188-." Then if you are not able to work them out at once on reaching home, you will not forget whence they came. ”

“ Tiny shells buried in sand can be netted in your sieve. Clinging ones must be chiseled off rocks. Frail, delicate clingers should be gently nudged loose with tweezers. Submerged sandbars are good spots to find several kinds of univalves and bivalves, but the latter will dig themselves quickly out of sight—as far down as several feet. When you see one going underground, don't dig directly over it—you might break its shell. ”

“ Supporting this evidence, we have freshwater or littoral shells found at great depths off our coasts. Mr. Godwin Austen records the dredging up of a freshwater shell (Unio pictorum) off the mouth of the English Channel between the fifty fathom and 100 fathom lines, while in the same locality gravel banks with littoral shells now lie under sixty or seventy fathoms water. ”

“ It happens, however, more frequently that the organic substance itself has disappeared, but has left an impression on the rock, that now bears witness to its former presence. Thus, for instance, when a shell has been dissolved and carried away by water percolating the rock, it has very often left after it, on the hard stone, a mould of its outer surface and a cast of its inner surface, with a cavity between corresponding to the thickness of the shell. ”

“ If we attribute to the shellmound an age representing many centuries, cultural differences should be indicated in the successive strata. For it is impossible that the cultural state of one and the same place should have remained stationary for many centuries and, even judging by the mass alone, the mound could not have reached such a height in less than a considerable number of centuries. ”

“ Everyone who has spent a little time in naturalising on the shore, has noticed how often you may find univalve shells, such as those of the whelk and periwinkle, with the top of the shell knocked off. This is nearly always the case with the dead shells that you find strewn along the tide-line; and after a storm, on a rocky coast, you may find shells that still contain the living tenant, in the same sad condition. And you may also meet not infrequently with shells, dead or living, that bear evidence of the owners' efforts to repair them after an accident to the spire. ”

“ Shell Beds.—What the circumstances are, which favour in a special degree the accumulation of shells on the bed of the sea, may be partly conjectured; but the subject deserves to be considered as one of the most important problems which geology looks to the naturalist to resolve. Very different conditions are known to govern the aggregation of the different tribes: they choose different soils—so to speak love—different depths, bear unequally the influence of currents, fresh water, climate. ”

“ There are so many possibilities to be encountered that the question of age is lost among them. The growth of a shell-heap depended, of course, upon the number of people living in the vicinity, whether their residence was continuous or occasional, the abundance or scarcity of shell-fish, and many other accidents too numerous to mention. Layers of soil in different portions of the same heap show that portions of the mass ceased to grow for long periods of time, while thick strata of clean shell indicate the rapid and continuous growth of other portions. ”

“ In examining the implements of successive layers of the mound we find that awls and certain knife-like tools found in nearly all known shellmounds are met with in all of the strata, while ornaments consisting of Haliotis shells and other simple objects of decoration made of shells, corresponding in general appearance to those which are still in use among the Indians, are met with in the graves of the VIth to the VIIIth strata. In the deepest strata, however, there have not been found any bone beads, ornaments of Haliotis shells, or saw-like tools such as are known above the VIIIth stratum. ”

“ At almost any point of the coast of the Isle of Wight, in bands of limestone and beds of clay, in cliffs of sandstone or of chalk, we shall have no difficulty in finding numerous shells. But it is not only in the rocks of the sea coast that shells are to be found. In quarries for building stone and in the chalk pits of the downs we see shells in the rock, and may often notice them in the stones of walls and buildings. ”

“ Not a single shell seems to have become extinct during the last six thousand five hundred years! The shells which lie embedded in the subsoils beneath the old coast-line are exactly those which still live in our seas. ”

“ The evidence of the marine origin of the highest drift is no doubt inconclusive in the absence of shells, so great is the resemblance of the gravel and sand of a sea beach and of a river’s bed, when organic remains are wanting; but, on the other hand, when we consider the general rarity of shells in drift which we know to be of marine origin, we cannot suppose that, in the shelly sands of Moel Tryfaen, we have hit upon the exact uppermost limit of marine deposition, or, in other words, a precise measure of the submergence of the land beneath the sea since the glacial period. ”