TRANSACTIONS OF THE SECTIONS. 67 
_ for water were also detailed: in these the depths at which water was 
found are very variable—namely, 237 feet, 299 feet, 86 feet, 60 feet, 
58 feet, and the alternations of sand, clay, siliceous rock (called by the 
author Jasper), exhibit at short distances considerable irregularity. 
On certain Phenomena connected with the Junction of Granitic and 
Transition Rocks, near Christiania in Norway. By CHARLES 
Lyet., #.R.S. (communicated by L. Horner, F.R.S.) 
It has been long known by geologists that granite occurs in the 
~ neighbourhood of Christiania in Norway more modern than the schist 
and limestone, containing trilobites, orthocerata, and other fossils of 
the transition period. It is also, I believe, the prevailing opinion that 
this granite offers an exception to the general rule, and that it covers 
the fossiliferous formations in large overlying masses, in the same 
manner as is commonly the case with basalt, and other members of the 
_ trap family. I found, howeyer, on visiting this summer with Pro- 
fessor Keilhau several points where the junction of the granite and 
transition strata is well seen, that the phzenomena agree precisely 
_ with those usually exhibited where granite comes in contact with other 
_ rocks, and sends veins into them. M. Keilhau had already come to 
this conclusion, after examining the whole line of contact of the 
granite and fossiliferous beds, and in this respect my observations 
_ went no further than to verify and confirm his statements. It is true 
_ that in some places near Christiania the granite may lean somewhat over 
_ the edges of the transition beds, and be for several yards incumbent 
Ne. " on them (as at a. 
No. 1); but not 
by any means so 
as to resemble the 
overflowing trap 
rocks. Nor was it 
from such appear- 
ae ances thatthe over- 
_ lying position of the Christiania granite was first inferred, but rather 
from the manner in which the strata of schist and limestone frequently 
_ dip towards the granite up to the point of contact, appearing as if they 
would pass under it. (See No. 1.) When, however, these strata are 
_ traced up to the granite, they are seen to terminate abruptly ; and no 
instance is known to Professor Keilhau, in this country, of a large mass 
_of granite regularly overlying strata containing organic remains. 
‘The different varieties of granite in this part of Norway have been 
described by Hausmann, Von Buch, and others. They are chiefly 
yenitic, but must all be classed by the geologist as granite, presenting 
e usual characters of that family of rocks both in small specimens 
and mountain masses. This syenitic granite seems to pass in some 
_ regions into trap porphyry, but it is only where the rocks have assumed 
= 
Granite. 
