402 Mr. J. Phillips's Geological Observations made 



2. Diluvial deposit consisting of pebbles and sand and clay 



spread indiscriminately over the surface of the strata. 



3. Red and white marl with layers of gypsum. 



4. Upper limestone in thin lamina?, with hardly a trace of 



magnesia ; and few or no organic remains, except at the 

 bottom. 



5. Red and blueish-white clay with layers of gypsum. 



6. Magnesian limestone in thick beds, some of which abound 



in organic remains. 



7. Yellow or purple sand and sandstone used for moulding 



at the iron-works. 



Beneath are the shales and sandstones of the West Riding 

 coal district. 



My remarks will be confined to the limestone and red marl 

 formations, and to the diluvial and alluvial accumulations 

 which cover them. 



No. 6. — The yellow magnesian limestone is in this country 

 a fine-grained rather powdery rock, never indurated to mar- 

 morean hardness as at Roche Abbey, nor composed of granu- 

 lar rhomboidal crystals as in the southern part of Notting- 

 hamshire. It exhibits in one of the Weldon (marries a re- 

 markable course of siliceous nodules, of an irregular oval figure, 

 lying in one continuous bed of stone, like a layer of flints in 

 a bed of chalk. No organic body is connected with them. 

 When accidentally thrown into the limekiln they suffer fusion 

 on the surface, in consequence of the lime which surrounds 

 them, and become coated with porcelain or solid transparent 

 glass. In this quarry the hollow sparry concretions so com- 

 mon in the magnesian limestone lie in layers in the upper part 

 of the rock. No fossils are seen here; but between this place 

 and Ferrybridge, Mr. Richardson collected a considerable 

 number. 



On the road from Ferrybridge to Pontefract, and near to 

 the latter place, the magnesian limestone has been cut through 

 in the road, and exhibits the hollow balls of calcareous spar 

 in great variety and profusion. While I was occupied in ex- 

 tracting some of these from the south bank at the brow of the 

 hill, an angular red substance fell down with the debris of the 

 loose limestone, which upon examination surprised me very 

 much; for it was rock-salt. (May 31, 1826.) My inquiries 

 on the subject produced nothing satisfactory. The specimen 

 is in the cabinet of the Yorkshire Philosophical Society. 



In the same road, nearer to Ferrybridge, divided veins of 

 sulphate of barytes may be seen crossing the loose beds of 

 magnesian limestone in a north and south direction. This 

 rock sinks regularly beneath the town of Ferrybridge, and is 



covered 



