252 WHIRLY PITS. 



&c., injurious and even fatal to animal existence : in 

 summer all these baneful exhalations are neutralized 

 and rendered wholesome by the vast quantities of oxy- 

 gen, or vital air, discharged from vegetable foliage : but 

 these agents of benefit, by the autumn, are no more-^- 

 consequently the discharge of oxygen is suspended, but 

 the production of unhealthy air increased by the addi- 

 tional decomposition of the season. To counteract this, 

 is probably the business of the storms of wind and rain 

 prevailing at this season, which, by agitating and dissi- 

 pating the noxious airs, introduce fresh currents, and 

 render the fluid we breathe salubrious. The same may 

 be advanced in regard to spring: the whole decay of 

 winter, having no neutralizing body to render it whole- 

 some, requires some great influencing power to remove 

 it. But all this is reasoning without actual evidence ; 

 a discursive license, from the fallibility of human judg- 

 ment not often to be indulged in : yet we can so rarely 

 perceive the purport of the movements of nature, that 

 our conceptions, vague as they may be, are almost all 

 that remain to us. 



We have here so few operations of nature deserving 

 mention, that I must not omit to notice a rather uncom- 

 'mon appearance in some of our clay-lands, which the 

 surrounding parishes do not present. The soil of a few 

 fields seems to cover for some depth a rock of coarse 

 limestone, which we never burn for use. In a direction 

 bearing nearly east and west, in a line pointing to the 

 Severn, a number of sinkings and pits are observable, 

 like abandoned shafts, or the commencement of mines. 

 They are called by the country people " whirly pits." 

 In some instances the bottoms of them are not visible, 

 owing to the tortuous irregularity of the passages ; in 

 other cases they are only deep hollows, covered with 

 turf. These sinkings are evidently occasioned by the 

 towering of the surface in consequence of the removal 

 of the support beneath. Where the under parts have 

 been entirely displaced, the upper have fallen in, and 

 formed a chasm ; where only partially removed, deep, 

 turfy hollows are formed. These removals have been 

 occasioned, probably, by a stream of water running far 



