126 Mr, H. J. Brooke on a substance named Bleiniere, 

 The first pair of relations may be changed into 



tt, = ,^, + W2 + z/3+M4=v,-f-f + -,^+--- 



Vj t'g V^ 



84= 2(u- •) = 2(«,«s«8) = 1 + Hi + ^ + 1>5, 



Vj Vg Vg 



or otherwise varied, as may the other two pairs. These results 

 will perhaps throw light upon the question of the solvibility of ■ 

 the equation in s. If e(a7), e{x)j &c. can be determined, the 

 general equation of the fiifth degree admits of finite algebraic 

 solution. 



IQ Cambridge Terrace, Hyde Park, 

 June 13, 1866. 



XVII. On a substance named Bleiniere in modern Treatises on 

 Mineralogy, By II. J. Brooke, F.R.Si"^ 



THIS mineral, which is described as having been hitherto 

 met with only at Nertschinsk in Siberia, has been recently 

 found in Cornwall by Mr. Richard Tailing, of Lostwithiel. 



It is uncertain from what ores the Nertschinsk mineral has 

 been produced, but the Cornish variety appears to have resulted 

 from the decomposition of Jamesonite. 



The Siberian mineral appears to vary considerably in the pro- 

 portion of its constituent elements. 



Hermann found the specimen which he analysed to be com- 

 posed of — 



Protoxide of lead . . . 61-83 

 Antimonic acid . . . 31*71 

 Water G-46 



Other specimens were found by PfafF and Hermann to contain 

 variable proportions of arsenic acid ; and a reddish-brown spe- 

 cimen from Siberia, recently examined by Mr. Allan Dick, at 

 the Museum of Practical Geology in Jermyn Street, contains a 

 large proportion of arsenic without any trace of antimony. Dif- 

 ferent portions of the Cornish mineral have also been analyised 

 by Mr. Dick, and are found to vary in their composition so much 

 as to render it probable that no two specimens would furnish the 

 same results. 



One portion consisted of — 



Oxide of lead .... (PbO) 4073 

 Oxide of antimony . . (SbO^) 47*36 

 Water 11-91 



* Communicated by the Author. 



