308 Royal Institution : — Prof. Roscoe on Vanadium, 



reliable information respecting the character of vanadium, have only 

 served to throw doubt upon some of the conclusions of Berzelius, 

 and thus to show that our knowledge is even less complete than it ap- 

 peared to be. 



Hence it was with much satisfaction that in February 1865 the 

 speaker came into possession of a plentiful source of vanadium in a 

 by-product obtained in the preparation of cobalt from the copper- 

 bearing beds of the lower Keuper Sandstone of the Trias at Alderley 

 Edge, in Cheshire. The manager of the works was puzzled to know 

 why a blue solution, supposed by him to contain copper, did not de- 

 posit the red metal upon a strip of zinc ; the speaker recognized this 

 reaction as due to the presence of vanadium, and secured the whole 

 of the by-product, which he found to contain about 2 per cent, of 

 the rare metal. The exact position of the vanadium mineral in the 

 sandstone beds cannot now be stated, as the mine (at Mottram, St. 

 Andrews) from which the cobalt ore was obtained is now closed and 

 cannot be entered. The general characters of the deposit, however, 

 are well known, and exhibit points of great interest ; they have 

 been well described by Mr. Hull as follows : — 



" The ' edge ' or escarpment of Alderley rises from the eastern 

 side of the plain of Cheshire gradually towards the east, but with a 

 steep and abrupt ridge towards the north. This northern bank is 

 richly wooded, and has a very beautiful aspect when viewed from a 

 distance, as it contrasts strongly with the almost level plain which 

 sweeps away to the northward and westward from its base. The 

 ridge has here been upheaved along the line of a large fault, bear- 

 ing east and west, throwing down at its base the red marl, and on the 

 other side bringing up the soft sandstone of the Bunter, capped by 

 a mural cliff of lower Keuper conglomerate, which often breaks out 

 in conspicuous masses through the foliage. The beds rise from 

 the plain towards the east at an angle of about from 5° to 10°; and 

 the escarpment is continued southward for some distance facing the 

 east." 



Succession of Beds in Descending Order (Hull). 



Red marl J Red and gray laminated 



I, marls. 

 Brownish flaggy sand- 



Waterstones ) T TZ 



Freestone / ^™£ per 



Copper-bearing sandstone [ | ™ c « n ' ' 

 Conglomerate j ee ' 



Upper red and 

 sandstone . . . 



mottled I 



Bunter. 



stones and marls. 



White and brown free- 

 stone. 



Soft white, yellow, and 

 variegated sandstone. 



Hard quartzose conglo- 

 merate, underlain by 

 bands of marl, form- 

 ing the base of the 

 Keuper sandstone. 



Soft fine-grained yellow 

 and red sandstone, 

 being the uppermost 

 member of the Bun- 

 ter sandstone. 



