GEOLOGY. 187 
coasts terraces rising like steps, one above another, often occur. 
Their outline and composition should be studied, diagrams made of 
them, and their height measured at many and distant parts of the 
coast. There is reason to believe that in some instances such terraces 
range for surprisingly long distances at the same height. Where 
several occur on opposite sides of a valley, a spirit-level is almost 
indispensable in order to recognise the corresponding stages. 
The evidence of depression, on the other hand, unless there are 
buildings or trees partly sunk in the water, is much less readily 
obtained, and neither trees nor buildings are available as evidence, 
unless the depression be of comparatively recent date. The best 
proof is the form of the coast. If inlets of moderate breadth occur, 
with numerous branches, a little examination will frequently show 
whether such inlets are valleys of subaérial erosion, as is not 
unfrequently the case, that have been depressed below the sea. In 
higher latitudes, care must be taken to distinguish the features of 
glacier valleys, like the friths and lochs of Scotland, and the fiords 
of Norway, from those valleys of subaérial erosion that have recently 
undergone subsidence. It is highly probable, even in the case of glacier 
valleys, that they were originally formed by fresh-water denudation, 
and that they have been depressed, though their features may have 
been modified by the action of ice. 
In conclusion, it may be re-urged that the geologist must bear in 
mind that to collect specimens is the least, though a very important, 
part of his labour. If he collects fossils he can hardly go wrong; if 
he be so fortunate as to find the bones of any of the higher animals, 
he will, in all probability, make an important discovery. Let him, 
however, remember that he will add greatly to the value of his fossils 
by Jabelling every single specimen, by never mingling those from two 
formations, and by describing the succession of the strata whence they 
are disinterred. 
