The stratum immediately below the chalk, (No. 3.) is a coarse, brown, pebbly sand, consisting of quartz and oxyd of iron, varying in thickness from six to ten yards, and of uncertain appearance at its denudation. While the different strata in these parts were exposed to the action of the water, the sand would naturally be more affected by that element than the superincumbent stratum of chalk; and the latter being thus left projecting, would from the decomposing effects of the atmosphere, crumble down, and form those various declivities which now present themselves to view.
Beneath the sand is a bed, about fourteen yards in thickness, (No. 4.) containing equal proportions of oolite limestone and calcareous clay of a light grey colour. In some parts the stone is divided by the clay into regular strata, whilst in others it occurs in large detached pieces imbedded in the clay. Fossil shells, and lumps of pyrites, or sulphuret of iron, are frequently met with in the stone.
The next stratum (No. 5.) consists of grains of quartz, for the most part agglutinated into sandstone of different degrees of induration, and varying in colour from a light grey to a dark brown, whilst in some parts loose sand predominates. In the grey variety of this stone, marine shells of different kinds, are found in great abundance: in the brown they occur very seldom, and not at all in the sand. This stratum is considerably thicker than the two incumbent ones.
The lowest visible stratum is the shale, [100a] (No. 6.) which generally makes its appearance in vallies. As it no where exhibits a denudated termination, its thickness cannot be estimated, but from the great depths in which it has been bored, without being perforated, it must be immense. [100b] A great variety of organic remains are also found in this stratum.
The last division to be considered is an alluvial collection of earth, almost entirely consisting of the spoils of the neighbouring strata in a state of decomposition, wherein however detached pieces of the different strata are to be found unaltered. From this it appears that when these parts were deluged by the water, the current set in from east to west. As the chalk and the shale would present the largest surfaces to the erosion of the water, they would be more extensively acted upon than the other strata: hence the greatest part of the alluvial deposition consists of white marle and blue; the former (No. 7.) being of the least specific gravity, has covered the hills, while the latter with sand gravel (No. 8.) occupies the lower parts.
NATURAL HISTORY.
In the department of Natural History, this district possesses but little which is deserving of particular notice. Of birds there are none which can now be considered peculiar to this part, the drainage of the fen lands having entirely banished the great variety of aquatic birds which used, previous to that event, to be found here.
A variety of plants, many of which are of rare occurrence in other parts, are indigenous to this neighbourhood: a list of them is given in the following table.
| Names of the Plants.
| Where found.
|
| Achillea ptarmica
| Bridle road to Hemingby
|
| Agrimonia eupatoria
| Ditto.
|
| Alchemilla vulgaris
| Ditto.
|
| Alisma plantago
| Ditto, wet ditches.
|
| Allium ursinum
| Tetford Wood.
|
| Anemone nemorosa
| Tetford and Thornton Woods.
|
| Antirrhinum linaria
| Horncastle, dry banks.
|
| Arabis thaliana
| Ditto, sandy grounds.
|
| Artemisia vulgaris
| Ditto, long hedge.
|
| Artemisia absinthium
| Tetford.
|
| Arum maculatum
| West Ashby.
|
| Asperula odorata
| Tetford, Stovin, and Whitehall Woods
|
| Asplenium adiantum
| Tattershall.
|
| Berberis vulgaris
| Scrivelsby, Horncastle,
|
| Betonica officinalis
| Tetford and Stovin Woods,
|
| Bryonia dioica
| Horncastle, West Ashby.
|
| Campanula trachelium
| Tetford Wood, Revesby.
|
| Cardamine hirsuta
| Bridle road to Hemingby.
|
| Carduus marianus
| Stovin Wood, Kirkstead.
|
| Centaurea scabiosa
| Horncastle, long hedge.
|
| Chironia pulchella
| Ditto, Blind lane, Scrivelsby road.
|
| Cichorium intybus
| Revesby.
|
| Cineraria palustris
| Sturton.
|
| Comarum palustre
| West Ashby furze-hill.
|
| Cornus sanguinea
| Horncastle, woodcock-lane.
|
| Convallaria majalis
| Bardney.
|
| Cynoglossum officinali
| Martin, Thornton.
|
| Crepis biennis
| Thornton, West Ashby.
|
| Digitalis purpurea
| Holbeck, Salmonby.
|
| Dipsacus sylvestris
| Horncastle.
|
| Drosera longifolia
| Tattershall.
|
| Drosera rolundifolia
| Ditto.
|
| Echium vulgare
| West Ashby.
|
| Erica vulgaris
| Moor.
|
| Erysimum alliaria
| Poolham.
|
| Eriophorum angustifolium
| Bridle road to Hemingby.
|
| Eupatorium cannabinum
| Tetford.
|
| Frugaria vesca
| Somersby.
|
| Galeobdolon luteum.
| Tetford and Stovin Woods.
|
| Genista anglica
| Horncastle.
|
| Gentiana amarella
| Greetham, Hemingby.
|
| Gentiana pneumonanthe
| Tattershall Park.
|
| Geum rivale
| Horncastle, wet meadows.
|
| Geum urbanum
| Ditto, banks of the Old Bane.
|
| Galium saxatile
| Moor.
|
| Hedysarum onobrychis
| Golceby.
|
| Hottonia palustris
| Thornton Mill.
|
| Hydrocotyle vulgaris
| Bridle road to Hemingby.
|
| Hyosciamus nigrum
| Hemingby, Baumber, Roughton.
|
| Hypericum audrosæmum
| Tattersall.
|
| Hypericum perfoliatum
| Ditto.
|
| Hypericum pulchrum
| Tattershall.
|
| Hypericum elodes
| Bridle road to Hemingby.
|
| Hydrocharis morsus ranæ
| Ditto.
|
| Iris pseudacorus
| Bridle road to Hemingby.
|
| Jasione montana
| Horncastle.
|
| Ligustrum vulgare
| Edlington, West Ashby.
|
| Linum perenne
| High Tointon.
|
| Lonicera periclymenum
| Holbeck, Roughton.
|
| Lycopsis europæus
| Horncastle.
|
| Lysimachia nemorum
| Roughton.
|
| Lythrum salicaria
| Thornton mill.
|
| Lychnis flos cuculi, var. flor. alb.
| West Ashby furze-hill.
|
| Malaxis paludoso
| Moor.
|
| Melampyrum pratense
| Tetford and Stovin Woods.
|
| Menyanthes trifoliata
| Horncastle.
|
| Myrica gali
| Moor.
|
| Ophyris apifera
| Mareham-le-fen.
|
| Ophrys ovato
| Thornton Wood.
|
| Oxalis acetosella
| Tetford Wood.
|
| Ophioglossum
| Langton, Stixwold.
|
| Ononis arvensis
| Horncastle.
|
| Orchis mascula
| Tetford and Thornton Woods.
|
| Orchis maculata
| Ditto.
|
| Orobus tuberosus
| Daw-Wood.
|
| Parietaria officinalis
| Horncastle Church, Kirkstead Abbey.
|
| Paris quadrifolia
| Tetford Wood.
|
| Parnassia palustres
| Horncastle.
|
| Pedicnlaris palustris
| Ditto.
|
| Pinguicula vulgaris
| Tattershall.
|
| Polygonum bistorta
| Horncastle.
|
| Poterium sanguisorba
| Ditto.
|
| Primula elatior
| Thornton Wood.
|
| Pyrethrum parthenium
| Wilksby.
|
| Ranunculus flammula
| Ditto.
|
| Ranunculus lingua
| Woodhall wharf.
|
| Reseda luteola
| Tetford Wood.
|
| Rhamnus catharticus
| Thimbleby.
|
| Rubus idæus
| Wood at Somersby.
|
| Sagittaria sagittifolia
| Thornton Mill.
|
| Salvia verbenaca
| Horncastle.
|
| Sanicula europea
| Stovin and Tetford Woods.
|
| Saponaria officinalis
| Baumber, West Ashby, Horncastle.
|
| Scandix pecten veneris
| Hemingby.
|
| Scilla bifolia
| Thornton Wood.
|
| Scrophularia aquatica
| Bridle road to Hemingby.
|
| Serratula tinctoria
| Thornton, Stovin and Tetford Woods
|
| Solanum dulcamara
| Horncastle, Golceby.
|
| Solidago virga aurea
| Tattershall.
|
| Spartium scoparium
| West Ashby, Harrington.
|
| Spirea fillipendula
| Bridle road to Hemingby.
|
| Tamus communis
| West Ashby.
|
| Tanacetum vulgare
| Salmonby, Golceby.
|
| Teucrium scorodonia
| Holbeck, Salmonby.
|
| Tormentilla repens
| Bridle road to Hemingby, Scrivelsby.
|
| Trachelium majus
| Revesby.
|
| Tussilago farfara
| Horncastle.
|
| Tussilago hybrida
| Horncastle, Hemingby.
|
| Tussilago petasites
| Horncastle.
|
| Typha latifolia
| Tetford.
|
| Vaccinium oxycoccum
| Moor.
|
| Valeriana sylvestris
| Horncastle, Tattershall.
|
| Verbascum
| Tetford Wood.
|
| Verbena officinales
| West Ashby.
|
| Vinca major
| Salmonby.
|
| Viola albus
| Edlington.
|
| Viola canina
| Tetford Wood.
|
| Viola hirta
| Ditto.
|
| Viola tricolor
| Holbeck, Salmonby, Tetford.
|
Minerals occur rarely in this part, and in very small quantities. Lumps of sulphuret of iron in the oolite stratum, earthy oxide of iron and prussiate of iron in a valley at Salmonby, and a stalactitic oxide of iron in the ferruginous gravel, comprise all the varieties which have yet been found.