or scratched with a lnrd substance, and on that account has been 

 called by the miners, Hell-fire rock. 

 % It proves upon examination to be an almost perfectly pure car- 

 bonate of lime, containing occasionally slight impurities of iron, 

 etc. It is a loose grained, white, crystalline limestone, the grains 

 of which are but slightly coherent, giving the rock the appearance 

 of a soft sandstone. Upon slight abrasion in the hand, it crumbles 

 to form a coarse, calcareous sand. Under the microscope the rock 

 appears as a loose mass of irregular, angular grains, which are 

 nearly transparent, and which have a luster resembling that of 

 alum. Portions of the rock are colored slightly yellow by oxide 

 of iron. 



Its phosphorescent properties are very remarkable, entitling it 

 to rank as a new variety of limestone. It was long ago noticed 

 by Becquerel that some limestones were slightly phosphorescent, 

 but so far as known, no other limestone possesses this property 

 in a degree at all approaching that now described, the phosphor- 

 escence of which is nearly as strong as that of fluor spar. 



Phosphorescence is developed when the rock is either struck, 

 scratched or heated. Upon using metal, glass or any other hard 

 substance to strike or to scratch it, a deep red light is emitted, 

 which continues sometimes for several seconds after the blow. 

 Rubbing with other fragments or grinding in a mortar developed 

 a white light. The most remarkable phosphorescence is developed 

 by heating a fragment of the limestone in a glass tube over a 

 flame. It then glows with a deep red light which lasts for a 

 minute or more after withdrawing the flame. The color of the 

 light emitted resembles that of a red hot body. Several seconds 

 before dying out, the light becomes white or bluish-white. Upon 

 cooling and subsequent heating, phosphorescence is again de- 

 veloped in the same fragment, but much more feebly and for a 

 shorter period, and after two or three such he ttings, its phosphor- 

 escence is destroyed.—//. C. L. 



Proceedings of the Mineralogical Society of Great 

 Britain and Ireland— The Mineralogical Society of Great 

 Britain and Ireland, instituted in 1876, holds general meetings in 

 London two or three times a year, and an annual meeting at the 

 time and place of the Britisli Association meeting. Local meet- 

 ings may also be held at any time and place. Its proceedings are 

 issued as occasion may demand. The number before us, dated 

 May, 1882, contains the following papers, read at the meetings of 

 December 23, 1880, and September 2, 1881. 



Minerals new to Ih-itain.— Professor Meddle contributes analyses 

 of the following British minerals :, Halloysite, fibrolite, martite (ap- 

 parently altered magnetite), turgite (pseudomorphous after py rite), 

 xonaltite (resembles a granular pink chalcedony), schiller spar 

 (mixed with serpentine), hydrous saussurite ('?), lachylite (a fused 

 dolerite), dolerite, pitchstone, spherulite, paulite (hypersthene), 



