GEOLOGY AND MINERALOGY. 495 



described by Dr. Jenzsch, exhiliit a brilliant metallic lustre, AYithirou-black colour 

 and unchanged streak. H. about 4.0 ; Sp. gr. = 6.451. 



Magnoferrite. — Rammelsberg proposes this name for the so-called octahedral 

 iron-glance from Vesuvius: a combination, according to his analyses, of sesqui- 

 oxide of iron and magnesia. Specimens varying in sp. gr. from 4.56 to 4.65, yield- 

 ed results closely approaching to sesqui-oxide of iron 85. 'Zl, magnesia 14.29; and 

 sesqui-oxide of iron 84.21, magnesia 15.79. The former corresponds to 2 MgO, 

 3 Pe^O^ ; tiie latter to 3 MgO, 4 Fe^O^. Magnoferrite must not be confounded 

 with the well-koowu specular iron ore from Vesuvius, which occurs in thin leaves 

 and small crystal aggregations. A specimen analysed by Rammelsberg, yielded: 

 sesqui-oxide of iron 98.05, magnesia 1.40. The formulae given above throv?- the 

 jnagnoferrite out of the great Magnetite and Spinel series, a somewhat unexpected 

 result. The term Talcoferrite or Magnesioferrite appears to us less likely to 

 create misconception, than that bestowed on this substance by Rammelsberg. 



Franklinite. — This mineral has also been newly analysed by Rammelsberg with 

 results somewhat different from those previously obtained by Abich, and by 

 Dickersoii. The mean of several analyses shewed : sesqui-oxide of iron 64.51, 

 oxide of maganese 13.51, oxide of z"nc 25.30. There results =3 RO, R'^0^, a 

 formula considered by Rammelsberg to be isomoiphous with the spinel formula 

 EO, R203. 



Cerite. — Rammelsberg has also analysed several specimens of Cerite witli the 

 following (uiean) results: Silica 19.18, oxide of cerium 64.55, oxides of lanthanium 

 and didymium 7.28, lime 1.35, oxide of iron 1.54, water 5.71. The oxygen-ratios 

 of the water, pi'otoxides, and silica = 5,09, 11.17, 9.96 — from which Rammelsberg 

 deduces the formula 2 RO, SiO- + HO. As the earlier analyses of Hisinger and 

 Hermann shewed respectively 9.60 and 9-10 per cent, of water, vchilst those of 

 Kjerulf and Klaproth shewed 5.29 and 5.10 per cent., agreeing closely in that 

 respect with his own, Rammelsberg starts the question as to whether there nray 

 not be two distinct minerals included under Cerite. This mineral, however so 

 rock-like in its characters, is exactly one of those in which we might expect to iind 

 a certain diversity of composition. 



Boracite and Sta.tsfurthile. — Dr. Julius Potyka has analysed examples of these 

 substances. His analyses give for Boracite, the formula 2 ("3 MgO, 4 BO-') +. Mo- 

 CI ; and for Stsssfurthite, the same with one atom of water. The latter is identical 

 witli that previously deduced by Heiutz. 



Triphylline. — A new analysis of this mineral (from Bodenmais in Bivaria) has 

 been published by F. Oestea. This analysis, which seems to have been very care- 

 fully perforated and on pure m.aterial, leads to the same formula as that given by 

 Fuchs, viz. : 3 RO, PO*. This differs very materially from the results obtained by 

 Rammelsberg. 



Classification of Meteorites. — An interesting classification of meteorites has 

 been drawn up by the Baron von Reichenbach. It is too long for insertion in the 

 present place, but a condensed analysis of it will be given in our next series of 

 N'otes. 



PUBLICATIONS. 



The following publications, in this department, have been received since the last 



