312 
with the creation ; others supposing them to have obtained their 
present forms at the reformation of the world, after the deluge ; 
whilst others conjecture, that their formation is going on at the 
present day. That many of them have been formed at periods later 
than the creation of the world, is rendered indisputable, by the 
various impressions of organized substances which they bear. The 
strongest evidence which has been adduced as to their more recent 
formation, is that of Dr. G. Gardner, of Aberdeen, contained in a 
paper published in the Philosophical Transactions* ; he relates, 
that, “upon the river Don, a little below the bridge, upon the 
river’s mouth, there is a bank, the face of which is broken down ; 
and it is full of stones, which one would think were in Jieri; they 
are all either round or oval, of different sizes j the faces of most of 
them are broken off, they are soft, and will easily rub down with 
your hand; they are of different grits and colours, and are made 
up of different sands and clays mingled together ; the clay is soft, 
both to the hand and taste ; in some of them, white, in others, grey, 
though, in some places, the clay and sand are hardened to a very 
considerable degree.” Dr. Gardner proceeds to remark, that they 
bore a very near resemblance to such oval stones as we see in the 
fields ; and that where they were softest, the bed which each stone 
laid in, was always hard, and of another grit and colour. It is 
however by no means improbable, that the pebbles here described 
might be in a state of decomposition. The pebbles of which the 
pudding-stone is chiefly formed, generally yield such an appearance, 
as may be supposed to have been the effect of pressure, whilst they 
existed in a soft state ; and we have a curious instance, related by 
the celebrated Bergman, illustrative of this circumstance — a moun- 
tain of pudding-stone, in the lower strata of which, the pebbles 
shewed evident marks of having suffered compression, being re- 
* Philosophical Transactions, Vol. XV. No. 175 , 
