Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/483

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at Hackness, was a frequent visitor at Knapton; and experiments were conducted which, demonstrated the great value of the material for agricultural purposes. Serious thoughts were at one time entertained of working this seam of phosphatic nodules ; but its thinness and the amount of bearing which required to be moved in following the bed led to the abandonment of the scheme. I obtained specimens of these nodules; and they are identical in every respect with those which have of late years been so extensively worked at Speeton Cliff, and which, as shown by Mr. Leckenby, mark the boundary between the Neocomian and Jurassic formations. Taking into account the identity in character and thickness of this seam of phosphatic nodules with that worked at Speeton, the similarity in every respect of the pyritous clays in both localities, immediately overlying it, and the similar septaria in both, occurring at a little higher level and crowded with the same species of Ammonites, I think there can be no doubt that we have here at Knapton the junction of the Neocomian and Oolitic clays. At this place a boring was many years ago put down to the depth of 500 feet, the only strata pierced being beds of blue clay (Kimmeridge). It is quite in conformity with our views of the relations of the strata of the Vale of Pickering, that at Settrington and North Grimston, a little to the west of Knapton, we find the Kimmeridge clay lying immediately at the foot of the Wolds. The same formation is again found at several points along the north side of the Vale of Pickering, as at Kirkby Moorside, where Ostrea deltoidea, Sow., (which I have shown to be characteristic of the lowest Kimmeridge beds,) occurs. The clays of the two pits at Knapton were formerly dug for the purpose of supplying material to a brickyard in the village, but they have not been worked for many years.

It will thus be seen that in their inland development the Upper and Middle Neocomian of Yorkshire have afforded no sections, the strata being covered by a great thickness of drift; of the Lower Neocomian, however, several of the beds are exposed inland at Reighton, West Heslerton, and Knapton ; and at the last-mentioned place we observe the junction between the Neocomian and Jurassic beds. The relations of the strata of the Vale of Pickering are illustrated in the accompanying sketch map (Pl. XXIII. fig. 3), and in the section (fig. 2) drawn along the escarpment of the Wolds.

III. The Neocomian Iron-ores op Lincolnshire.

In 1867 I described the Middle Neocomian, or Tealby Series, of Lincolnshire as containing beds of valuable iron-ore. Since that date the West Yorkshire Coal and Iron Company have opened a mine near Acre House, between Claxby and Nettleton, and the expectations that I entertained of being able to obtain new light on the stratigraphical relations and the fossil-contents of these very interesting beds have been to some extent realized.

The existence in this district of fragments of iron-slag, calcined ore, and charcoal, associated with Roman pottery, indicates that these ores were known and worked at a very early period.

The only ironstone in this district which is now found suffi-

VOL. XXVI. PART I. 2A