MINERALOGY OF FRANKLIN. 279 



characters which are generally considered to be pe- 

 culiar to minerals which have been affected by a 

 great heat. 



Without pretending to account here for the cause 

 of this interesting appearance, we merely state the 

 fact, and proceed to lay before the Academy the re- 

 sult of our observations, which we shall divide into 

 two parts. The first shall include the geological 

 description of Franklin and its neighbourhood. The 

 second shall contain an account of the minerals 

 which are found at that locality. This second part 

 we shall subdivide into two chapters. In the first 

 we shall make known the new mineral species which 

 we have discovered. In the second we shall give 

 an account of the new varieties of mineral species 

 found there. 



PART FIRST. 



REMARKS ON THE GEOLOGY OF FRANKLIN. 



The Franklin iron works are situate in Sussex 

 county, at about seven miles and a half to the north- 

 east of Sparta, two miles south-west of Hamburgh, 

 and eleven miles east of Newton or Sussex Court 

 House. The works are located at the spot where the 

 metalliferous ridge, which we propose to make the 

 principal object of this description, is intersected by 

 the valley, in which run the head -waters of the 

 Wallkill, a stream which after swelling to a consi- 

 derable size, empties itself into the Hudson, at Co- 

 lumbus. 



