444 Miscellaneous. 



At Huel Bassett the occurrence of ' Cassiterite ' is omitted ; at 

 Pengelly of ' Millerite.' 



At Stenna Gwynn ' Wavellite' is named in mistake for * Tavis- 

 tockite' (vide new edition of Dana). 



The occurrence of ' Senarmontite' is not mentioned at Endellion. 

 'Uranochre' has never been found at the Eoyal Eestormel iron 

 mines, but only the ' Bismufchochre,' while ' Eestormelite' is omitted. 



Several important mines have been overlooked entirely, e.g., 

 ' Silver Vein,' near Lostwithiel, in which is found Argentiferous 

 Tetrahedrite ; the 'St. Austell Consols,' producing Chalcopyrite, 

 Kupfernickel, Cobalt, and Pitchblende ; and ' Lanescot' or ' Fowey 

 Consols,' in which occur Chalcopyrite, Chalcotrichite, Magnetite, 

 Chalybite, Cassiterite (Wood-tin), Kupfernickel, Cobalt, Bismuthine, 

 Millerite, Melaconite. 



I would ask Mr. Hall why he uses the name ' Towanite' throughout 

 his book instead of ' Chalcopyrite,' or Copper Pyrites, as the names 

 are not synonymous, the former having been given by Greg and 

 Lettsom to the modification found at Huel Towan ; and also why he 

 calls 'Limonite,' 'Limnite.' Limonite is derived from the Greek 

 T^ifioov, a meadow, and is almost exclusively applied to the Brown 

 Iron Ores ; while ' Limnite,' from \l/j,vr], a marsh, is applied to the 

 Yellow and Stalachtitic bog iron ores. To these varieties are given 

 distinct formulae in Dana's last edition, and, therefore, they may be 

 regarded as species for the present. 



Apologizing for intruding on your valuable space I am, etc., 



Bbackley, August 22, 1870. B. J. E. 



IMIISCEXjXj-A-lsriEOTJS. 



New British Locality foe Avantukinb-quartz. — This scarce 

 variety of quartz has recently been observed by Mr. G. W. Traill in 

 Orkney, on the S. and S.W. shores of Inganess Bay. It occurs in 

 the form of small rolled pebbles, seldom exceeding an inch in 

 diameter, but well marked, and occasionally fit for ornamental pur- 

 poses. The colour is usually reddish-brown, but sometimes yellow. 

 The scales of mica are very numerous, of a golden colour, small, 

 uniform in size, and generally disposed in parallel planes as if they 

 had settled in a liquid ; but in a few of the specimens this regular 

 arrangement does not appear. The reddish-brown variety is very 

 compact, takes a high polish, and has a specific gravity of 2-62 ; the 

 yellow is of a fine granular structure, and has a specific gravity of 

 2-60. This appears to be almost the only well-ascertained British 

 locality for avanturine-quartz ; and, as the rocks in the neighbour- 

 hood are entirely sandstone, the situation is somewhat peculiar. 



The Congress of Alpine Geologists which was to have been 

 held at Geneva, on 31st August and the 1st and 2nd September, is in- 

 definitely postponed, owing to the present unsettled state of Europe. 



