Geology, ^-c. of the Connecticut, 31 



ing it in several places, is to pass by the right hand road from 

 Belchertovvn congregational meeting-house, to the meeting- 

 house in Ludlow. 



The narrow deposite of sienite which is first mentioned 

 above, as occurring in Whately, is somewhat different in its 

 characters. Let the observer proceed northerly on the 

 main road from the congregational meeting house one mile, 

 till he comes to the farm of a Mr. Crafts. On the left hand 

 side of the road he will find a ledge of rocks which are 

 greenstone slate, nearly allied to hornblende slate, and some- 

 times to chlorite slate. Let him cross these strata westerly, 

 about fifty rods, and he will come to a deposit of decided 

 unstratified primitive greenstone, about twenty rods wide. 

 Immediately succeeding this rock, he will find the sienite 

 above named. It consists of nearly equal proportions of 

 felspar and hornblende, the latter of a dark green and of a 

 distinctly crystalline structure; and the former white and 

 compact or very finely granular, entirely destitute of a foli- 

 ated structure, or pearly lustre. These ingredients seem 

 to be promiscuously blended, and the rock appears to be 

 peculiarly well adapted for being wrought and polished for 

 useful and ornamental purposes. The bed is not very ex- 

 tensive, only about six rods wide at the place above men- 

 tioned, and I have never been able to trace it more than one 

 or two miles. It is separated from the mica slate by a nar- 

 row stratum of greenstone slate. 



Sienite, or sienitic granite, occurs in maiiy other places 

 along the Connecticut; but in no other place have I found 

 it extensive enough to deserve a place on the map, except 

 perhaps in Chatham, and with the relative situation of this I 

 am not sufficiently well acquainted. Where I have crossed 

 it, it appeared to form a bed in porphyritic hornblende slate. 



8. Primitive Greenstone. — Cleaveland, 



Colored Carmine or Rose Red, and mrtrked [by parallel lines 

 crossing each other. 



This is one of Werner's varieties of primitive trap. If it 

 beasked whatthatis,! should suppose Mr. Maclure's supposi- 

 tion to be not an improbable one, that "what Werner calls 

 primitive trap may perhaps be compact hornblende; or per- 



