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as gilded, where both the rocks and the earth are so splendid to behold that better inducement than ours might have been persuaded they contain more than probabilities. The vesture of the earth in most places doth manifestly prove the nature of the soil to be lusty and very rich.
* In Summer, no place affordeth more plenty of sturgeon; nor, in Winter, more abundance of fowl in the time of frost. I took once fifty-two sturgeon at a draught, at another sixty-eight. From the latter part of May till the end of June are taken few, and they are but a yard long. From then, till the middle of September, they are seldom less than two yards long; and in four or five hours, with one net, there were ordinarily taken seven or eight. In the small rivers there are, all the year, plenty of small fish; so that, with hooks, those that would take pains have sufficient.
Such great and well proportioned men are seldom seen, for they seem like giants to the English, yea, and to their neighbors, yet seemed of an honest and simple disposition, and, with much ado, restrained from adoring us as God.”
Washington and Georgetown, and, indeed, the whole District, is underlaid with gneiss rock, the trend of which is nearly east and west. Throughout the City of Washington and its suburbs the rock is covered to a greater or less depth with a tertiary formation of mineral matter, a considerable part of which is drift. The drift in some places consists of sandstone, limestone, jasper rock, quartz in boulders, pebbles, gravel, sand, clay, and loam. The mixture of loam and clay often abounds in a peculiar
DISTRICT OF COLUMBY
state of aggregation, as if the clay and loam had been at first separate, and in masses of considerable size, and
these ultimately thrown into a confused mass. Such is the character of the ground on English Hill, on East Branch, just below the Navy Yard, about the brick kilns, between the Navy Yard and the arsenal.
This character of the tertiary is well adapted to the manufacture of brick, and constitutes the basis of this manufacture in Washington. The parts A, A, A, in the sketch, represent the gneiss rock, which was originally compact and, apparently, durable, and, as found in the neighborhood of Little Falls, some two miles above Georgetown, it is extensively quarried, and used in cellar and foundation walls, and other coarse work. It splits in two directions nearly at right angles to each other, which fits it for faced work with little labor. There is one peculiarity in this rock, however, which renders it very uncertain as a durable stone. In certain locations it goes to decay rapidly, and disintegrates entirely in a few years. The rock, as it exists on the Virginia shore of the Potomac at Little Falls, has so broken down along the road side that a rod may be forced
into it in some places for two feet from the surface, by the thrust of the arm. It is not so throughout, but only in certain localities. The cause of this peculiarity has not been investigated. It is proper to say, with regard to the underlying gneiss rock of the Potomac valley, that the rock does not appear at the surface at all the places marked A; but, from the appearance and features of the surface, it is evidently there; and it contributes to make and shape the contour of the surface. To the eastward and northeastward, the valley of the East Branch constitutes a flat river bottom which receives the drain from the contiguous banks and lands. As we proceed along the east side of the Potomac, from the Capitol toward the north and northwest, the rock first makes its appearance parallel with the river (that is, the trend or line of the ridge of the rocks), in the vicinity of Pennsylvania Avenue where it crosses Rock Creek, which forms the dividing line between Washington and Georgetown.
Georgetown lies virtually at the head of tide-water, although the salt water does not ascend nearer than forty or fifty miles. Georgetown, therefore, is at the junction of the tertiary and primary rocks, and at the last fall of the river, before it plunges into positive tide-water. Georgetown may be said to rest on the primary gneiss, while Washington, though evidently resting on the same base, has its substratum so low, by the dip of the rock beneath the surface, that it may be properly, and is generally, called tertiary, on account of the accumulation of clays, sands, and drift that have been piled upon it to the depth of many hundred feet, and which belong to the deposits of the tertiary formation. No considerable borings in the way of artesian wells have been made, so as to
decide at what depths the rock is reached from the surface in the different parts of the City of Washington. Suffice it to say, that the results obtained from such excavations as have been made by digging wells and cutting down hills show a great variety of mineral matter and of successions of deposit.
We will speak first of the deposits as geological, then of the mineral matter, referring to the sources of it. At the lowest point penetrated, say 40 to 50 feet, we find successive beds of clays, sands, peaty earth, exogenous woods, in fragments, and silicified; others not silicified, but in a lignitous state; others containing pyrites of iron; but these are confined to certain localities covered with water. In drier parts, where pyrites have been formed, the pyrites have undergone a decomposition, and the iron has become peroxydized, and shapen in various forms, according to that of the original nucleus. Thus we frequently obtain, in excavating, balls of iron, sand, or clay, like cannon-balls in form, but very light; and on breaking them open we find within the remains of a pine-knot or other vegetable matter, around which the sulphate of alumina or of iron had originally formed, on the carbonaceous matter. Subsequently the sulphur of the compound has been removed, and left the iron predominating in the state of iron-sand cemented together.
In 1856, or thereabout, in excavating I Street, at the junction of New Jersey Avenue, a log of silicified wood was removed at a depth of about 22 feet below the original surface. It was fully silicified throughout, with the strong marks of the grain of exogenous wood, of structure closely resembling the oak. It had crystals of quartz on its surface in great abundance.
The various strata of these deposits, especially the lowest, had evidently been deposited in quiet waters, as at the bottoms of lagoons or ponds, or stagnant pools where were first sand or gravel, then clays, then peat matters charged with iron; then, perhaps, some of these deposits repeated, and finally covered with ten or fifteen feet of drift. In all cases, the drift is on the top, and is very irregular in its character, generally consisting of masses or clumps of broken-up clay and loam, and pebbles, irregularly thrown together; and these constitute the mass of earth as found in the excavations of the streets in Washington and its suburbs. Clay, however, is the predominating earth throughout almost the whole District where the rock is covered with tertiary matters. The iron, being quite abundant and soluble in the carbonic acid of the air, is absorbed in the falling rain and surface water into the ground, and gives an iron deposit in nearly all water drawn from pumps and wells, conferring a degree of hardness which renders it objectionable for domestic uses. The debris of the broken-down gneiss rock gives a clear, micaceous loam, that does not abound in clay; hence, the hills about the District are more like other primary lands. The distinctive character of the mineral matter found in the tertiary of the District has been the result, not of one uniform action, but of several successive and different actions, and with long intervals between, in which peat and other vegetable growth has accumulated these followed by sudden inundation of sands or gravels, &c., and these at last by vast accumulations of drift. In all cases, the deposit was from an older formation; and we find amongst the drift limestone and sandstone, in pebbles of various sizes, in rolled masses. In