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STRATA IDENTIFIED BY ORGANIZED FOSSILS,
containing prints on colored paper of the most
CHARACTERISTIC SPECIMENS IN EACH STRATUM
By WILLIAM SMITH, Mineral Surveyor,
Author of Map of the Strata of England and Wales, and A Treatise on Irrigation.
Printed by W. Arding, 21, Old Boswell Court, Carey Street;
And sold by the Author, 15, Buckingham Street, Strand; J. Sowerby, 2, Mead Place,
Lambeth; Sherwood, Neily, and Jones, and Longman, Hurst,
Rees, Orme and Brown, Paternoster Row;
And by all Booksellers
June 1, 1916
The present age is distinguished by many of the most extraordinary discoveries that were ever unfolded to the human mind; and amongst them the discoveries in Chemistry stand pre-eminent The most extensively useful part of this science has, however, been long before the public, and contributed greatly to the improvement of various branches of manufacture; but the benefits of Chemistry have not yet been extended to the soil,
Agriculture in this, as in most other instances, is the last to profit by any think new . That easy analysis of the soil, which seemed to promise great advantages to the Farmer, by telling him correctly the component parts of the materials he has to work upon, has not been spread through the country, or even yet become an object of attention with many of the best informed Farmers, by whom the advantages of this science must be carried into effect; and while the theory is in the possession of one class of men, and the practice in another, who have little or no connexion, it is greatly to be feared, that the culture of land may long remain without its expected benefits from Chemistry.
In a similar way, also, the benefits resulting from the science of Botany, have been equally limited, and likely to remain so until those who grow the grasses shall take the trouble to distinguish one form another, or until those who know them scientifically shall condescend to become the cultivators.
Nature furnishes the clue to each of these sciences, and to the most extensive application of their benefits.
She had also given the Farmer other more easy helps, to much of the useful knowledge he requires.
The method of knowing the Substrata from each other by their various substances imbedded, will consequently shew the difference n their soils, All this is attainable by rules the most correct, and easily learnt, and also the simplest and most extensive that can well be devised; for by the help of organized Fossils alone, a science is established with characters on which all must agree, as to the extent of the Strata in which they are imbedded, those characters are universal; and a knowledge of them opens the most extensive sources of information, without the necessity of deep reading, or the previous acquirement of difficult arts.
The organized Fossils (which might be called the antiquities of Nature) and their localities also, may be understood by all, even the most illiterate: for they are so fixed in the earth as not to be mistaken or misplaced; and may be as readily referred to in any part of the course of the Stratum which contains them, as in the cabinets of the curious; and, consequently, they furnish the best of all clues to ta knowledge of the Soil and Substrata.
The practicality of thus distinguishing so great a variety of materials in the earth, as successively terminate at the surface being admitted; and their courses delineated in a large map of the Strata just published; I may now confidently proceed with a general account of those organized Fossils, which I found imbedded in each stratum, and which first enabled me more particularly to distinguish one Stratum from another.
Fossil Shells had long been known amongst the curious, collected with care, and preserved in their cabinets, along with other rarities of nature, without any apparent use. That to which I have applied them is new, and my attention was the first drawn to the, by a previous discovery of regularity in the direction and dip of the various Strata in the hills around Bath; for it was the nice distinction which those similar rocks required, which led me to the discovery of organic remains peculiar to each Stratum. Their perfect state of preservation, and most tender structure, raised a doubt respecting their diluvian origin, and a close attention to the Gravel Fossils, clearly proved two distinct operations of water.
The Fossils of the former deposit being all finely preserved, which those of the latter, (which are chiefly superficial,) are all greatly rounded by attrition. Those of the first class are never found but in their respective sites in the Strata; those of the latter, by their promiscuous mixture, superficial situation, and other circumstances, most strongly conform the previous deposit, and complete induration of the Strata which contain the former. Conceiving, therefore, the Gravel Fossils to be the most indubitable effects of a great body of water pouring over the surface of the earth, with violence sufficient to tear up fragments of the Strata, round them by attrition and drive them many miles from their regular beds to the promiscuous situations which contains tem being thus clearly distinguished from the regular Strata beneath, much of the mystery in which Fossil Shells , and other materials of the earth were involved, seemed to be removed by this distinction.
Thus far it may be necessary to apprise the reader of the meaning here attached to the word alluvial.
The organized Fossils which come under that head, being as various as the Strata from whence they have been dislodged, and account of them will most properly be given in the last number. Under the same head, also, will be given, further particulars of the Frontispiece, of annexed Engraving of a singular Fossil Tooth, of some extinct monstrous unknown animal, which is opalized;found in Norfolk.
(pages 1 and 2)
WITH ORGANIZED FOSSILS
THE eastern and south-eastern half of
England, as for inland as a curved line from Exeter to Teesmouth, abounds with organized
Fossils, regularly imbedded in the Strata. The vast expanse of red Marl and its Sandstone,
has none of them, but they are very abundant in the Limestones which accompany it.
These, however, occupy but a small portion of the island, compared to the great extent of Strata before-mentioned, and when it is considered that in the remainder of the Strata, Red and Dunstone, Killas and Granite, organized Fossils are not found, or very rare; they seem chiefly confined to the district before described, and to the Coalmeasures, and the bituminized wood of blue clays, in the other districts, being trifling exceptions to general rules so extensive.
The eastern side of the island is, therefore, best for the commencement of regular observations on the organized Fossils which are illustrative of its Geology. It is also necessary that the series of British Strata, for the simplification of science, should be considered in classes. The part above the Chalk is one, and the principle divisions of which it is susceptible, are reducible to twoa great Sand and a great Clay, with a general parting of Crag; but each of these is subject to considerable variations.
The Sand lies next the Chalk, and the clay over that forms insular hills.
The great Sand is in many places interspersed with Clay, or Brickearth, and the Clay as frequently with Sand and Loam. Pebbles are common to both, but to what depth beneath the surface my be difficult to determine
The chief partition Strata have not always the same appearance. The Craig being, in some [arts of its course, composed of shells and sand, in some places of shells and clay, and in others of shells and coral, united in a soft stony rock, which about Oxford is used in building. In other places the shells are filled with, and imbedded in a hard blue grey Sandstone, and in some of their course they appear to be deficient, or found only thinly interspersed with a blue grey concreted loam, or indurated Brickworth. The alluvial Pebbles, Clay, and Sand spread over great breadths of the plains formed by the surface of these thin partition Strata, much increases the difficulty of tracing their outcrops.
The greatest breadth of the Clay is in Essex, and the vicinity of London, as described in my delineation of the Strata by the dun or dark blue colour, and the localities of the most remarkable sites of its organized Fossils, are noted in a list which accompanies the explanation of the plate.
The other great division of Sand and Brickearth, is represented on the map by yellowish brown, and the sites of its peculiar Fossils under the head of Craig, similarly describedbut the partition Strata which produce these shells, vary so much in hardness, colour, consistence, and uses, as to render a local description of one part, almost unintelligible to those who are acquainted with it in another. For on a cursory view of these shelly Strata in their course through  the three north-eastern countries, from the banks of the Thames, some miles below London, it is singular that a considerable distinction in the site or accompaniments of the shells should be peculiar to each of the countries.
The shells in Essex are lodged in a strong blue Clay which makes a tenacious soil.
All through Suffolk in a light or blowing Sand, which, in many parts of the course of Crag, is some of the worst land in the country.
Through Norfork the shells lie much nearer to, or in contact with the top of the Chalk, and under a loamy soil, on or near some of the best land in Fleg and the Vale of Aylesham.
In the present state of our knowledge of these Strata, and the shells they contain, any attempt at a minute division of them, seems, therefore, more likely to perplex, than instruct the reader
The strong features only of the country, will therefore, first be noticed, The order of nature which is shown by my discoveries, suggests the outline of the work, and the different Strata serving like chapters for the principle divisions, the subject will be so treated; taking each of their outcrops in succession. from East to West. The figures of organized Fossils in each Stratum are printed on coloured paper, to correspond with the most general colour of the matter in which they are imbedded, and also with that by which their courses are represented on the Map; where otherwise, as in the Chalk, it will be particularly noticed under each head.
It may be necessary to remark, that the Strata over Chalk, occupy much of the eastern, south, and south-eastern coast of England, and seem to be only parts of much larger districts of corresponding Strata on the Continent.
In England this class is separated into three portions, by vacancies on the heights of Hampshire, and in the sea by the Wash. The mouth of the Humber makes also a lesser division but for these, the class might be said to extend from Dorsetshire to Yorkshire, for Pool Harbour is in one extremity, and Bridlington Bay in the other.
The northern-most of the three principle portions, North and South of the Humber, is small, long, and narrow, lying low, and as yet little noticed for organized Fossils, except large bones washed out of the crumbly cliffs of Holderness, which correspond with those washed out of similar cliffs on the coast of East Norfork, Suffolk, Essex, East Kent, and South Hants.
The middle and principle portions extends north-eastward from the Hampshire Hills to the coast of Norfork; it flanks the Chalk through Surrey and Kent, on the south side of the Thames; the Buckinghamshire and Hertfordshire Chalk Hills on the north side. It embraces the whole Estuary of the Thames; spreads over nearly all Essex, three-fourths of Suffork, and all the eastern half of Norfork, except the Vales about Norwich and Aylesham.
The northern portion, chiefly in Hempshire and Dorsetshire, narrows both ways from its widest part about the new Forest, to its western extremity, near Dorchester, and its eastern, near Brighton. Its widest part is from Newport in the Isle of Wight, to the similar elevations of Chalk and down lands, between Salisbury and Winchester. Each of these districts is abundantly stored with organized Fossils, Large teeth and bones, great resembling those on the Continent, have been most frequently collected from the shores of the middle portion, and large vertebrae further inland, at Whitlingham, Leiston old Abbey, Diss, Hoxney, and Hawkedon.
(pages 3 and 4)
|Soil. ||Colour, Orange brown, Y. R. B. 2, of Sowerbys Chromatic Scale, varying when wet.|
|Consistence,||Tenacious; free from Stone; dries clotty; cracks in drying; surface frequently covered with alluvial Pebbles.|
|Subsoil and Ditches, Retentive.
Excavations, Hold Water.
Stratum, Dry, of a dun colour. Darker when wet.
Water, Rarely any; the little which it produces of a bad quality.
THIS thick Stratum, from its being the site of the
Metropolis, and most abundant in its environs, has been called the London Clay. Its course
north-eastward to the sea is described in the Map, by the same colour as the plate annexed
The greatest length, from S.W. to N.E. is in a line passing from Richmond. through London to Harwich.
The greatest breadths. from Norwood Hill to Enfield Chase, and from Langdon Hills to the extremity of Epping Forest. It thence occupies the heights in the hundreds of Essex, and east of Chemsfrod and Colchester; extends through the Sokens to the sea side at Walton Nase, and Harwich.
The soil is of a mellow brown or umber colour, and the subsoil generally the same, although the Stratum deeper (as lately shown by tunnels under London,) is of the colour by which I have endeavored to represent it.
The exact boundaries of soft Strata are generally difficult to define, but particularly so in this district, where they alternate with no hard materials in the form of Rock.
Outcrops also of such loose Strata, are too confused for the Geologist to avail himself of the distinctive advantages to be derived from their peculiar imbedded Fossils, as throughout the district over Chalk, they are found only in deep excavations.
The shelly part of the London Clay bears but a small proportion to the thickness of the mass. The shells, therefore, should rather be considered as Indices to the site of that particular part, than to a knowledge of the whole. They lie near the bottom of the Stratum, and in some instances are difficult to be distinguished from those of the Crag, which accompanies the sand.
Arca Linn, Pectunculus Lam.
Large Shark's tooth
|Well at Brixtom Causeway. Hordwell Cliff.
Woolwich. Bracklesham Bay.
LONDON CLAY. Sowerby's Mineral Conchology.
Fusus Longaevus, Tab. 63. Barton and Hordwell Cliffs. Muddiford.
Vivipara lenta, Tab. 31. Fig. 3. Barton and Hordwell Cliffs.
Nautilus Imperialis, Tab. 1. Highgate. Brentford. Minster Cliff. Isle of Sheppy.
Modila elegans. Tab. 99. Bognor. Highgate. Richmond.
Venericardia planicosta, Tab. 50. Bracklesham Bay.
Teredo antenautae. Sheppey.
Sowerby's Mineralogy. Tab. 14. Pag. 33.
Argilla Marga, containing shells. Streatham, in Surry.
The Fossil shells of the Southern portion of this Clay, were first regularly described by Brander.
Those of the district round London, many years since excited much curiosity, from the great quantity turned up in digging the foundation of a house in Hanging Wood, near Woolwich.
They have, also, been found in sinking various wells around the Metropolis, but the recent excavations for a tunnel though Highgate Hill, brought them most into notice.
(pages 5 and 6)
CRAG is a local term for shells mixed with
sand, overlaying the Chalk, in the counties of Norfolk and Suffolk.
It is best known and most in use for agricultural purposes in the latter county.
It extends from Tattingstone Park south of Ipswich, through the East Sands or Flock district, to Henham Park west of Southwold.
Re-appears South and North of the Yare, below Norwich, at Bramerton and Thorpe, and has been found at Marsham in the vale of Aylesham, in its course to the sea side west of Cromer.
Crag is but a small proportion in thickness of the sandy Strata overlaying chalk.
Turbo Linn. Turritella Lam.
Thorpe Common, Harwich. Alderton, Suffolk.
CRAG. Sowerbys Min. Conch.
Scalaria similis, Tab. 16. Bramerton. Holywell.
Also at Newhaven Castle.
Several Fossil shells of this and the
Stratum preceding, greatly resemble some which arerecent. In the Clay they are generally
white, but some in the Crag, as Turbo littoreus, often retain their natural colour.
Oysters, of various sorts, found plentifully in the Strata over Chalk, seem to define the course of Crag at the following places:Headley, Reading. Woolwich, Blackheath, and in stone at Stifford, in a valley one mile south of Hertford, at Beckingham and Damerham, and in stone at New Cross, and Addington Hills, near Croydon.
Crabs and Lobsters are more numerous in these than in any of the inferior Strata.
Horns of very large animals are also found in low places, where these Strata approach the Marshes, which are considered to be alluvial.
Ivory has been collected from the sandy Crag; teeth, vertebrae, and other bones are numerous in it, some of these, and the shells being rounded and mixed with fragments of numerous imperfect shells, lead to an opinion that this part of the Crag may be alluvial. It is, however, traced through the same course of country, and if not connected with the stoney Crag, is so very contiguous thereto, as not to be separated in a general account.
The stoney calcareous Crag is in more regular layers than the sandy. In some places it appears to be covered with Brickearth. Shells are found perfect in this sort, which are probably only fragments in the other, and some perfect in that, are only casts in this, as the murex striatus of Sowerby.
Upper Oolite [ Middle Jurassic ]
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