THE MINERALS OF THE MIDLANDS. 203 



NORTHAIMPTONSHIRE. 

 " On Allophaue and an Allied Mineral found at Northampton,'' by 

 W. Douglas Hemian. (Quart. Jouni. Geo. Soc, vol. xxx.,p. 235). — " Dr. 

 Charles Berrill discovered a mineral resembling the Charlton 

 Allophane in physical properties in a pit opened in the ironstones of 

 the Northampton Sand, (Inf. Oolite), in the grounds of the Northamp- 

 ton Lunatic Asylum. It occurs as an amorphous, translucent, some- 

 what hard and exceedingly brittle mineral, of a yellowish colour, 

 inclining to red, and incrusting the surface of a sandstone rock. 



An.\.lysis. 



Northampton. Charlton. 



I. II. ilEAX. 



Water expelled at 100=C. . . 24-70 24-88 24-80 27-11 



Water tixed at lOO^^C. . . 14-54 14-54 14-54 15-80 



SiO^ .. 23-0!) 22-92 •2301 20-50 



Al^O^ .. 31-24 31-42 31-33 31-34 



Fe.203 .. 2-35 2-18 2-26 — 



FeO .. .— — — -31 



GaO .. 2-51 2-48 2-49 1-92 



MgO .. -01 -01 01 



Normal .. CO., .. 128 1-28 1-28 1-69 



As bicarbonate CO . . — — — 1"04 



99-72 99-71 99-72 99-71 



On the supposition that the mineral consists essentially of water 

 fixed at 100°C., silica, and alumina, it would be represented by the 

 formula 8A1^0g,15SiO., -f 18H.,0 ; but if the water that is given off 

 at 100° be considei-ed essential to its composition, it would be 

 expressed by Al^O ,2SiO., + 5H.,0. The mineral dried at 100° is 

 exceedingly hygroscopic, speedily regaining almost the whole of the 

 water it had lost, and that too in well-ground tightly-tittmg watch 

 glasses. Consult •' 3Iidland Naturalist," vol. v., p. 12. 



SHROPSHIRE. 



" Observations on the Wrekin and on the Great Coalfield of Shrop- 

 shire," by Arthur Aikin. (Trans. Geo. Soc, vol. i., 1811. p. 191).— The 

 references to mineral localities in this paper are so indefinite as to be of 

 no use. The curious band called Ciirlxton,'. occurring with the Penny- 

 stone iron ore at Ketley and the neighbourhood, is noticed at pp. 196-7. 



" Notice concerning the Shropshire Witherite," by Arthur Aikin, 

 Esq. (Trans. Geo. Soc, vol. iv., 1817, p. 438).— Refers to the Snail- 

 beach Mine as the only one in which witherite has been found. After 

 speaking of different ores it is stated that " in the lower part of the 

 mine, where the vein is thick and sparry, the witherite is found in 

 irregular masses, weighing from 401bs. to '2cv,'t. or 3cwt., imbedded in 

 heavy spar. It is called yellow spar by the miners, because if a 

 caudle is placed behind it the whole will glow with a yellowish light, 

 a circumstance by which the miners distinguish it from heavy spar ; 

 this latter, from the looseness of its texture, being in large masses quite 

 opaque. The colour of the witherite is white, -uath the slightest 

 possible, if any. tinge of yellow ; its fracture is broad striated, 

 approaching to straight foliated ; it is for the most part massive. I have 

 seen only a single specimen that presented any indications of a regular 

 crystalline form." On analvsis the mineral gave — 



