MANSFIELD: ROXBURY CONGLOMERATE. 131 
and conspicuous traces of glacial action. Plant remains show that 
in South Africa, the Indian Peninsula and Victoria these are of 
approximately the same age, and marine fossils show the same with 
regard to the beds of New South Wales and the Salt Range. The 
deposits in every case were formed during a period of great cold, 
which was succeeded by a much more temperate climate and it is 
almost impossible to doubt that this wide-spread change of climate 
must have been due to some far-reaching, if not cosmic, cause. 
Consequently it is justifiable to use the glacial deposits for the pur- 
poses of correlation and to conclude that the boulder beds of the 
three continents were formed contemporaneously.” 
——:— England. The conglomerate or breccia in the Upper Old 
Red Sandstone of England was believed by Ramsey to be of glacial 
origin. It has already been shown that the rocks in question are more 
locally derived than Ramsey thought and that they are in all probability 
of fluviatile origin. Nevertheless it is interesting to note the facts that 
led him to advocate the glacial idea. The arguments may be stated 
under four heads:— (1) Many of the fragments are of great size; the 
largest observed weigh one-half to three-fourths of a ton; (2) rounded 
fragments are exceedingly rare; the fragments are angular and sub- 
angular and have the flattened sides so characteristic of many of the 
glacial fragments of existing moraines; (3) many are highly polished 
and others are grooved and finely striated like the stones of existing 
glaciers; (4) the hardened cement, marl, may be compared to boulder- 
clay. 
:— Norway. At the head of the Varanger Fiord in northeast- 
ern Norway are some ancient glacial deposits, discovered and described 
by Reusch and later visited and commented upon by Strahan. Accord- 
ing to the latter (p. 140 et seq.), the thickness of the formation nowhere 
exceeds ten feet. The base is remarkably straight but the upper 
surface undulates and the overlying sandstone is deposited tranquilly 
upon it in such a way as to level up the irregularities. For an inch or 
two at the base the overlying sandstone contains material washed up 
from its surface. The formation itself is described as a “dark bluish 
or ashy gray, friable rock, composed of a heterogeneous mixture of grit, 
‚sand and clay, of all degrees. of coarseness and containing boulders 
ranging up to two feet in length scattered through it. Though quite 
unstratified, it shows here and there a slight schistose structure” 
(merely an obscure fissile structure is meant in consequence of which 
the rock splits more easily than in other directions; the microscope 
‚shows no crushing). “The included boulders, which are all shapes 
