64 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



chalk several inches long below the ^Deat, during an excavation 

 made for foundations of a chimney. This chalk may have fallen into 

 fissures of the limestone during the denudation of the Cretaceous 

 series, and have been washed out again at a comparatively recent 

 period. 



The quantity of gravel now left in the valley of the Aire may 

 only represent the portion of water-rolled debris arrested in transitu 

 to the sea, at a period when there occurred atmospheric changes of a 

 character and importance sufficient to reduce the flow of water to its 

 present insignificant amount. 



My object in selecting the gravel-deposit of the river Aire as an 

 illustration for examination is because that river fiows over a variety 

 of distinct strata, and yields evidence of the transport of a number 

 of large boulders from its source to near its outfall. Then its 

 source is in a district in which occur the celebrated caves of Kirk- 

 dale, so rich in the large Mammaha, such as Elephant, E-hinoceros, 

 Hippopotamus, and Hysena, and containing in the upper part of the 

 cave-deposits human skeletons and pottery. 



Although at Bingley itself no Mammalian remains have been 

 noticed, yet at Leeds, twelve miles lower down the river, the follow- 

 iijg description of the discovery of HippoiDotamus sufficiently iden- 

 tifies the Leeds gravel with the cave-gravel of the limestone district 

 by means of its organic remains, and with the Bingley gravel by 

 means of mineral character and stratigraphical position, 



Mr. H. Denny, of Leeds, records the discovery, on the 3rd of April 

 1852, of great portions of the skeletons of two or three large spe- 

 cimens of H'ppopotamns major at the angle formed between the 

 river Aire and Wortley Beck, close to Holbeck Station, Leeds, at 

 a height of 115 feet above the sea, and 20 feet above the banks of 

 the Aire. 



Mr. Denny writes, {' West Eiding Geological Society Eeports 

 for 1854,' p. 325) : — ^' The bones were discovered in a dark-blue 

 sedimentary clay almost approaching mud, and appear from their 

 condition to have belonged to animals which had lived and died in 

 the immediate vicinity, and were subsequently drifted, together with 

 fragments of trees to the bottom or lower part of a swamp, found 

 only in this particular bed of clay, confined to one portion of the 

 field ; but the clay becomes much thicker, and reaches 10 feet in 

 thickness as it approaches this spot, thus clearly indicating it to have 

 been lower than the remainder of the brickfield." 



Beds of clay of variable quality resting upon gravel, with occasion- 

 ally large boulders, some of which contain impressions of Stir/maria 

 and fragments of trees to the depth of 10 feet, yielded the bones of 

 three individuals of Hippopotamus major, whose skeletons seem to 

 have been complete when deposited. The canine tusk of one indivi- 

 dual was 18 inches long, by 2| broad. Mr. Denny observed that the 

 vertebral column of one Hippopotamus extended in a line across 

 the trench ; the ribs appear to have been in sita ; and from its posi- 

 tion he considered that the animal had been lying on its side. Por- 

 tions of the ElepJias primigenius, with molar teeth, and fragments 



