152 THE OLD RED SANDSTONE. 
servative qualities of the shales and stratified clays of the 
Lower Old Red Sandstone are not much inferior to those of 
lime itself; while, in the Upper Old Red, we have merely 
beds of consolidated sand, and these, in most instances, ren- 
dered less conservative of organic remains than even the 
common sand of our shores, by a mixture of the red oxide of 
iron. The older fossils, therefore, like the mummies of 
Egypt, can be described well nigh as minutely as the exist- 
ences of the present creation; the newer, like the compara- 
tively modern remains of our churchyards, exist, except in a 
few rare cases, as mere fragments, and demand powers such 
as those of a Cuvier or an Agassiz to restore them to their 
original combinations. But cases, though few and rare, do 
occur in which, through some favorable accident con- 
nected with the death or sepulture of some individual exist- 
ence of the period, its remains have been preserved almost 
entire ; and one such specimen serves to throw light on whole 
heaps of the broken remains of its contemporaries. The 
single elephant, preserved in an iceberg beside the Arctic 
Ocean, illustrated the peculiarities of the numerous extinct 
family to which it belonged, whose bones and huge tusks 
whiten the wastes of Siberia. The human body found in an 
Irish bog, with the ancient sandals of the country still at- 
tached to its feet by thongs, and clothed in a garment of 
coarse hair, gave evidence that bore generally on the degree of 
civilization attained by the inhabitants of an entire district in 
a remote age. In all such instances, the character and ap- 
pearance of the individual bear on those of the tribe. In at- 
tempting to describe the organisms of the Lower Old Red 
Sandstone, where the fossils lie as thickly in some localities as 
herrings on our coasts in the fishing season, I felt as if I had 
whole tribes before me. In describing the fossils of the 
