PRESERVATION 
15 
Kensington. Even soft jelly-fishes have left their mark on 
certain rocks ! At a place in Bavaria, called Solenhofen, there 
is a remarkably fine-grained limestone containing a multitude of 
wonderful impressions. This stone is well known to lithographers, 
and is largely used in printing. On it the oldest known bird has 
left its skeleton and faithful impressions of its feathers. 
The footprints of birds and reptiles are by no means uncommon. 
Such records are most valuable, for a great deal may be learned 
from even a footprint as to the nature of the animal that made it 
(see p. 41). 
Since the greater number of animals described in this book are 
reptiles, quadrupeds, and other inhabitants of the land, and only 
a few had their home in the sea, we must endeavour to try and 
understand how their remains may have been preserved. Our 
object in writing this book is to interpret their story, and, as it 
were, to bring them to life again. Each one must be made to tell 
its own story, and that story will be far from complete if we 
cannot form some idea of how it found its way into a watery 
grave, and so was added to Nature’s museum. For this purpose 
we must briefly explain to the reader how the rocks we see 
around us have been deposited ; for these rocks are the tombs in 
which lost creations lie. 
Go into any ordinary quarry, where the men are at work, 
getting out the stone in blocks to be used in building, or for use 
on the roads, or for some other purpose, and you will be pretty 
sure to note at the first glance that the rock is arranged as if it 
had been built up in layers. Now, this is true of all rocks that 
have been laid down by the agency of water — as most of them 
have been. True, there are exceptions, but every rule has its 
exceptions. If you went into a granite quarry at Aberdeen, or a 
basalt quarry near Edinburgh, you would not see these layers ; 
