ROCKS OF BRAZIL WOOD, CHARNWOOD FOREST. 245 
3ft. by 2ft. On examining the opposite or south end of the quarry, we 
here also found veins of granite running up the face and overlying the 
contortions before mentioned, and further small veins penetrating the 
rock even in the very centre of the quarry. At some points the line 
of junction of the two rocks was sharp and distinct, but at others the 
two appeared to be blended together for at least a few inches. Near 
the junction innumerable garnets were found to be developed in the 
gneiss, and a few occur also in the granite. Some of them exceed one- 
eighth of an inchin diameter, and are finely crystallised. 
At the north end of the pit we noticed, embedded as it were in the 
*‘oneiss,” four distinct patches of a bedded rock, resembling an altered 
ashy slate. These occurred one above the other at intervals of two or 
three feet, and had a north-westerly strike. These may be portions of a 
band of rock interbedded with the gneiss, and “ pinched” by it during the 
contortions which it has undergone. They reminded one of us of the 
banded ashy Charnwood slates. 
Ascending to the top of the knoll of gneiss we find a ridge 30 yards 
long, running N.N.W. by §.8.H. The northern end has been quarried 
into, but at the southern extremity we found an exposure of granite 
which is probably in situ, and represents the outcrop of another vein 
striking through the gneiss. The knoll is thickly covered with vege- 
tation, and many of the rocks are overlaid by a considerable thickness of 
moss; but we found a little cliff running along the S.W. side, which 
proved to be composed of a rock having a distinct cleavage, and to have 
the characters of an altered and slightly indurated clay-slate; it 
contains numerous small garnets. The cleavage is nearly vertical, 
and runs N.W. and §.E.; the strike, as far as we could detect, is afew 
degrees more to the west. This slaty rock is interbedded with a more 
compact and less cleaved bed. 
The discovery of these slaty rocks is another point of interest, as 
none have been previously observed to the east of the Swithland slates. 
The strike of the beds and their general appearance renders it almost 
certain that they belong to the Charnwood series, and we attribute their 
present crystalline structure to the action of the intrusive granite. 
We thus have in this small area an excellent exampleof the junction 
ofigneous with aqueous rocks, and of the gradual change produced in the 
latter as they approach theinjected mass, It is at present the only good, 
well- exposed, and readily accessible example with which we are 
acquainted in this district, for the line of junction in this area seems to 
be generally also a line of weakness, along which the rocks are shattered, 
so that they have readily decayed and left a hollow which is usually 
filled with soil; it is so, indeed, in this case, but the numerous veins sent 
forth from the granitic mass can here be clearly traced invading and 
altering the aqueous rock. 
These various rocks present several other points of interest, and 
their microscopical investigation has been undertaken by one of us, the 
results of whose work will probably appear in a future number. 
