boniferous Limestone, one branch coming from a cave near Gordale Scar, then flows over the very thick formation of Millstone-grit, reaches the Coal-measures between Shipley and Bingley, and, passing over the Magnesian Limestone and the New Red Sandstone, empties itself into the Humber, or a branch of the Humber, near Goole. The valley-gravel at Leeds is famous for the fine remains of Hippopotamus found in 1852. The bottom of the valley through which the Aire flows is from one-half to one and a half mile wide, and is coated over with a deposit of gravel and rolled boulders of unequal thickness and elevation, consisting principally of limestone at the upper part near Malham and Skipton, and of Millstone-grit and sandstone near Leeds, with some limestone boulders. The Bingley gravel consists of Millstone-grit, sand, rock, and limestone in large percentage. Some boulders of limestone are found near the mouth of the river near Goole; but at Bingley, fourteen miles from Skipton in a direct line, they form a considerable percentage of the whole gravel. Until the Leeds and Liverpool Canal was made between Leeds and Skipton, this valley-gravel was turned over for the purpose of removing the limestone boulders for burning into lime. There are numerous remains of old limestone-quarries and lime-kilns at Bingley, although it is ten miles from the nearest limestone rock.
Fig. 2 is a plan of the Aire valley between Bingley and Shipley, showing the lines of sections A B and C D from the sandstone-rocks on each side of the valley. (See Pl. IV. figs. 2 and 3, for details of the sections; and to these I will now refer.)
The section (fig. 4, Pl. IV.) through Ashfield, half a mile east of Bingley, exposes a thick gravel- and boulder-deposit, forming what are called the Old Hills. This gravel has been worked over for the blocks of limestone it contains, leaving an irregular surface.