HO W EXTINCT MONSTERS ARE PRESER VED. 1 7 
the light of the present, or, in other words, to find out what 
happens now, in order to learn what took place ages ago ; for it is 
clear that the world has been going on in the same way for at 
least as far back as geological history can take us. There has 
been a uniformity^ or sameness, in Nature’s actions ever since 
living things first dwelt on the earth. 
Just as rivers are mainly responsible for bringing down to the 
sea the materials of which rocks are made, so these universal 
carrying agents are the means by which the bodies of many 
animals that live in the plains, over which they wander, are 
brought to their last resting-place. We have only to consult the 
records of great floods to see what fearful havoc they sometimes 
make among living things, and how the dead bodies are swept 
away. 
Great floods rise rapidly, so that the herds of wild animals 
pasturing on grassy plains are surprised by the rising waters, and, 
being unable to withstand the force of the water, are hurried 
along, and so drowned. When dead they sink to the bottom, 
and may, in some cases, be buried up in the debris hurried 
along by the river ; but as a rule their bodies, being swollen by 
the gases formed by decomposing flesh, rise again to the surface, 
and consequently may be carried along for many a mile, till they 
reach some lake, or perhaps right down to the mouth of a river, 
and so may be taken out to sea. 
One or two examples will be given to show how important is 
the action of such floods. Sir Charles Lyell has given some 
striking illustrations of this. There was a memorable flood in 
the southern borders of Scotland on the 24th of June, 1794, 
which caused great destruction in the region of the Solway Firth. 
Heavy rains had fallen, so that every stream entering the firth 
was greatly swollen. Not only sheep and cattle, but even herds- 
men and shepherds were drowned. When the flood had subsided, 
a fearful spectacle was seen on a large sand-bank, called “ the 
beds of Esk,” where the waters meet; for on this one bank were 
c 
