13 



upon its enterprise, by spreading fertility and wealth to its remotest 

 boundaries. 



The superficial stratum of the region we are describing is an 

 argillaceous and ferruginous sand of a yellow and sometimes of a 

 reddish colour, in which are occasionally found at or near the sur- 

 face, pebbles and small boulders of sandstone, rarely as much as six 

 inches in diameter. The nature of these boulders would indicate 

 that they were most probably derived from the sandstone formation 

 which ranges along the eastern boundary of the primary ridge. In 

 some places this stratum consists of little else than a white silicious 

 sand ; in others, the admixture of ochreous clay is so considerable 

 as to furnish a suitable material for the manufacture of bricks. 



Beneath this superficial layer, beds of a very argillaceous clay 

 occasionally occur, sometimes of considerable depth and extent, and 

 of a texture to be useful in puddling. Its colour is various, being in 

 some places a dark blue or green, in others a bright red or dingy 

 yellow. Wherever found, its upper boundary is remarkably even 

 and horizontal ; but where it rests upon beds of fossil shells, its 

 lower limit conforms to all the irregularities of surface which those 

 beds usually present. Its appearance, in some places, is that of a 

 steep, almost perpendicular wall of smooth surface, and divided by 

 very narrow lines running horizontally. These narrow lines, at a 

 distance of from five inches to a foot asunder, are formed by a more 

 ferruginous and silicious clay. At Bellcfield, on the York river, 

 seven miles from Williamsburg, this deposite may be seen overlying 

 the stratum containing shells, in some places having a thickness of 

 from twelve to fifteen feet, and then gradually fining out and passing 

 into a light coloured and coarser mass. The upper surface is hori- 

 zontal, and the lines of division above alluded to are perfectly paral- 

 lel and regular. The lower surface of the clay conforms to that of 

 the shell stratum upon which it rests. In many places these argilla- 

 ceous beds consist of a yellowish clay, beautifully variegated by 

 streaks of red and blue. In some places there exists a slight impreg- 

 nation of alum and copperas in these beds of clay. This is particu- 

 larly the case in some localities on the Rappahannock and the York 

 and Chickahominy rivers. The proportion of these ingredients is, 

 however, not sufficiently great to entitle these strata to attention in 

 an economical point of view, although it is fully sufficient to impart 

 a very ungrateful flavour, and perhaps some useful medicinal pro- 

 perties to the springs and wells of the neighbourhood. 



