IN THE NEIGHBOURHOOD OF ALNWICK. 353 
basaltic action, and been subsequently broken up and scattered 
by denudation. The most decided case of far-travelled blocks in 
the Northumberland boulder beds is granite, which has, however, 
been but rarely observed. One large block of granite I have met 
with, measuring 8 cubic feet, neither worn nor rounded, embedded 
in clay on the western acclivity of Alnwick moor, at an elevation 
of upwards of 600 feet above the sea level, and of about 500 feet 
above the vale of the Aln below: this granite is identical with 
that, in situ, at Aberdeen. It is also important to notice that not 
one fragment of rock, of more recent age than the carboniferous 
formation, is to be found in the Northumberland superficial de- 
posits. 
From comparing a number of sections, it may be generally in- 
ferred that the superficial deposits of Northumberland have been 
formed under water, for the marks of successive deposit are dis- 
tinct, and the evidence of the moulding action of water is con- 
clusive. But these deposits are not separable into different eras : 
_ that is, it cannot be affirmed that the boulder clay is of a different 
age from the gravel and sand beds ; for it is sometimes found 
above and sometimes below them. Nor could one great debacle 
or wave of translation, or even a succession of them, have been 
the agents capable of producing the complicated phenomena ; for 
the finely laminated sands, which indicate tranquil deposit, are 
interstratified in various forms with the boulder clay. The whole 
indeed would seem to constitute one group, formed under water, 
during a long era, which was pervaded by the same general con- 
ditions, and acted on by the same mechanical agencies, subject 
to local modifications. 
Evidence of the conditions of this era, as to climate, must be 
had from organic remains. In Northumberland, I have carefully 
sought for this evidence, but hitherto without success. Reference, 
however, can be made to other districts where the same deposits 
are to be found. In Scandinavia there is a similar deposit; in the 
Isle of Man, the boulder formation overlies limestones of the same 
age as those in Northumberland ; and in the Valley of the Clyde, the 
formation is largely developed. Now, from all these districts 
organic remains have been found; some in a rolled and 
