Mineralogical Journey. 359 



lege to Prof. Silliman and myself. It did not, however, receive par- 

 ticular attention until recently ; when we had the pleasure of finding 

 it to contain, along with other things, two or three pieces of an appa- 

 rently sienitic rock, filled with beautifully distinct and nearly transpa- 

 rent crystals of Zircon, together with a small box containing a num- 

 ber of loose crystals of the same substance. The majority of them 

 are regularly terminated at one or both extremities. In size, they 

 vary from one inch in length down to a quarter of an inch, and in 

 diameter, from one eighth to one sixteenth of an inch. Their faces 

 are nearly all equally perfect as respects their evenness, and are pos- 

 sessed of a brilliant and somewhat adamantine lustre. In color, they 

 are uniformly of a reddish brown, not sufficiently bright to bring them 

 under the denominadon of Hyacinths, from which they differ, more- 

 over, in the character of their modificadons, as will be seen from a 

 view of the annexed figures. They approach in their general as- 

 pect, nearer to the variety of this mineral from Frederiksvarn in Nor- 

 way ; though they are not precisely identical with the crystals from 

 that place as respects their form. Fig. 2 is the Zircon plagiedre of 

 Haiiy, and fig. 3, the Z. binotriicnitaire, of the same mineralogist. 

 These are the only forms I could observe among the specimens in 

 my hands. The former of them is said to exist among the crystals 

 of Ceylon, while the latter has not before been known to occur ex- 

 cept at Trenton, N. J. where it was formerly found in a granite ap- 

 proaching in character to gneiss. 



I said that the gangue of the Zircon was apparently a sienitic rock : 

 such I am sure it would be pronounced in hand specimens seen at a 

 little distance. When viewed nearer by, however, the black lamellar 

 particles interspersed among the Feldspar and Quartz, are discovered 

 to be Magnedc Iron ore. Notwithstanding the absence of Horn- 

 blende which exists in the Norway rock, I am disposed to call it the 

 true zircon sienite. The Feldspar is of a greyish color often tinged 

 by the oxide of iron, and exists in small angular masses in nearly 

 equal proportion with the Quartz. 



As there were no tickets accompanying the specimens, I imme- 

 diately addressed a letter to Prof. Fowler, from whom I learned the 

 following facts. The specimens forwarded were detached from a 

 bowlder weighing about one hundred pounds, found one mile north 

 of Middlebury college, Vt. This mass is now in the possession of 

 Prof. F. The same rock occurs scattered over the surface in the 

 vicinity ; but " its proper geological position is upon the opposite side 



