86 Mr. J. Bryce's List of the Minerals of Dowti, fyc. 



to red flint. It consists of silica, alumina, water, lime, and peroxide of 

 iron. 



Abrazite, or Gismondine. — Recently found in small globular masses in the 

 Amygdaloid of Island Magee, by Mr. P. Doran. 



Epistilbite. — Recently found by Mr. P. Doran in the Trap of Rathlin and 

 Portrush. 



Clay Slate, Whet Slate, Drawing Slate, Alum Slate, Bituminous Slate, Clay- 

 stone, Tripoli, Slate Clay, Potter's Clay, Lithomarge, Fuller s Earth, 

 Green Earth, Mountain Soap, Bole, Wacke, Iron Clay. — Occur fre- 

 quently within the district. 



Steatite. — Frequent in the Primary and also in the Trap Rocks. 



Potstone. — Said by Sir C. Giesecke to occur in the Trap of Island Magee. 



Common Chlorite. — Occasionally with Quartz in Primary Rocks. 



Rock Cork and Rock Leather. —Occasionally between the strata of Chalk. [?] 



Emery. — Is said to occur in Mourne. 



Topaz and Beryl. — Are well known as occurring in the Granite of Mourne. 



Calc Spar. — Of various forms ; common everywhere. 



Satin Spar. — Frequent in Trap Rocks. 



Fibrous Arragonite. — Met with at Downhill and the Causeway. 



Calcareous Tufa and Stalactites. — Common ; the latter chiefly in Trap 

 caverns. 



Aphrite. — Is said to occur on the Transition Slate, Mourne. I have not 

 seen it. 



Agaric Mineral. — Lining Flint balls, Ballycastle, along with Rock Cork ; 

 also at Sleive Gallion in the same manner. 



Hydrocarbonate of Lime and Magnesia. — In the Amygdaloid of Downhill, 

 in spheroids having the appearance of a puddingstone. It is called by 

 Sir C. Giesecke, Hydrocarbonate of Lime. Dr. Thomson has discovered 

 Magnesia in it*. 



Rhomb Spar and Carbonate of Magnesia. — Occur in the Magnesian Limestone 

 at Holly and Belfast. The granular, compact, and fibrous varieties of 

 Gypsum and Selenite are found in various places in Antrim, in the 

 variegated Marl subordinate to the new red sandstone. 



Vulpinite. — I recently found this mineral in a Trap dyke at the base of the 

 Cave Hill near Belfast ; it is of a laminated structure and sky-blue co- 

 lour. Sir C. Giesecke mentions Rathlin as a locality, I know not on 

 what authority. 



Heavy Spar. — Occurs in Lead mines in several places ; also in the Old Red 

 Sandstone of Cushendun. Sulphate of Strontia is said to occur with it 

 in Newtonards lead mine. 



* Perhaps Mr. Bryce will inform us, in a future communication, whether 

 this mineral is allied to that which the late Mr. W. Phillips, at the sug- 

 gestion of Mr. Brayley, described under the appellation of Hydrocarbonate 

 of Lime, in the last edition (1823) of his Elementary Introduction to Mi- 

 neralogy, p. 161. " The latter mineral we are informed, in a communication 

 from Mr. Brayley, is the result of the action of the trap dykes of theGiants' 

 Causeway upon the chalk which they have intersected, and, according to 

 the analysis of the late Dr. Da Costa, would appear to be composed of 

 4 atoms carbonate of lime and 3 atoms water ; indicating, probably, that 

 the hygrometric water of the original chalk, under the combined influence 

 of heat and pressure, has entered into combination with the earthy salt: 

 or the water may have been derived from a former superincumbent ocean. 

 It would not be difficult to account for the formation of a similar hydrate 

 in the oavities of an amygdaloid, such as that alluded to by Mr. Bryce." 

 — Edit. 



