WHIRLY PITS. 
252 
&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 bum 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 
lowering 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 
