Intelligence and Miscellaneous Articles. 559 



deeply replaced. The approach to the form of phacolite is thus pro- 

 duced ; the edges and angles not standing out in relief, as they ordi- 

 narily do in these twin forms. The stria?, parallel with the edges of 

 the two rhombohedrons, so intersect as to show the compound nature 

 of the crystals. Dr. C. T. Jackson has a fine specimen of this va- 

 riety from the Two Islands, in Nova Scotia, of a wine-yellow colour ; 

 I have another pure white, from the same place. 



Yttro-cerite. 



This rare mineral is found, associated with brucite, in rolled masses 

 of limestone, in the town of Amity, Orange county, New York. I 

 have as yet seen but two specimens of it, which I found among 

 some fragments of limestone containing brucite and mica, in the 

 duplicate collections belonging to the late Dr. Horton of Edenville. 

 It attracted my attention as being unlike fluor spar, which it was 

 supposed to be at the time, and I have now satisfied myself that it 

 is yttro-cerite, though I have not gone so far as to detect the yttria, 

 the presence of which in the mineral cannot be indicated by mere 

 blowpipe experiments alone. It has no crystalline structure, but ap- 

 pears in thin layers or seams, which sometimes amount to scarcely 

 anything more than peach-blossom or purple stains, penetrating the 

 seams of the limestone : precisely the character of this mineral in the 

 specimens I have of it from Finbo in Sweden. With this it also 

 agrees in hardness and colour. When heated in a glass tube, it 

 slightly decrepitates, shows no phosphorescence, gives out moisture, 

 and becomes milk-white ; at the same time there is a perceptible 

 burnt smell. When its powder, moistened with sulphuric acid, is 

 placed in a platinum-crucible, hydrofluoric acid is given out by the 

 application of heat, and the usual reaction on glass is produced. The 

 pulverized mineral, heated with fused salt of phosphorus in an open 

 glass tube, also shows the same reaction, the glass losing its polish 

 where the moisture is deposited. In these experiments I was care- 

 ful to separate the mineral entirely from the brucite ; but I have not 

 been able to obtain fragments sufficiently free from carbonate of lime, 

 to enable me to give its blowpipe characters in detail, or subject it 

 to any other trials. I hope to be able to obtain better specimens at 

 an early day, and then to complete its examination. The mineral is 

 very characteristic, and, in the hand specimen, cannot be distinguished 

 from the Finbo variety. 



Ottrelite identical with Phyllite. 



The name of phyllite, from (j>v\Xov, a leaf, was given by Dr. 

 Thomson to a mineral which was discovered and sent to him for 

 analysis by Prof. Nuttall. It comes from Sterling, Massachusetts, 

 and is disseminated in small thin plates through what appears to 

 be an argillo-micaceous slate. Some of these plates are angular and 

 others rounded, not appearing to have any regular crystalline form ; 

 yet in a few instances they present the distinct form of rhomboidal 

 tables. Colour brownish-black, or grayish-black : lustre, shining and 

 semi-metallic ; opake; fracture uneven. The knife makes a faint 



