•72 



Scientific Intelligence 



density, while the glassy solid corresponds pretty closely to the 

 fluid in the same direction. These latter results are what were 

 to have been expected. — Jahrb. Min., ii, 14], 1901. 



Mineral or Rock. 



Melanite 



Augite 



Limburgite 



Lava, Etna 



Lava, Vesuvius 



Nephelinite 



Leucitite 



Original 



density. 



After 

 ignition. 



3*75 

 3-29 -3-3 



■ 2-83 

 2-83 

 2-83 -2*85 

 2-735-2745 



2-83 



Fluid. 



Rapidly 



solidified ; 



glassy. 



2-85-2-88 



2-84 

 2*84-2-87 



2-75 



3.55 -3-6 3-55-3-60 

 2-92 |2-92-2-95 

 2-55 -2-568 2-55-2-568 



2-586-2-74 J2-71-2-75 

 2-68 -2-74 i2-69-2-75 

 2-70 -2-75 I 2-686 

 2-60 -2 68 2-68-2-72 



Slowly 

 solidified; 

 crystalline. 



365 -3-7 

 3-2 -3-25 

 2-75 -2-78 

 2-81 -2-83 

 2-775-2-81 

 2-72 -2-75 

 2-75-2-787 



7. Das Siebengebirge am Rhein ; by H. Laspeyres, Mitth. 

 aus dem Min. Institut Univer. Bonn, xiiTheil. ; Verh. d. nat. Ver. 

 der preuss. Rheinl., lvii Jahr. 1900, Bonn 1901, 8°, pp. 471 with 

 color, geol. map and 23 tigs. — This work is a very careful and 

 detailed description of the local geology of the well-known 

 Siebengebirge. Since this is a volcanic group of mountains, so 

 the greater part of the memoir treats of the petrography of the 

 igneous rocks, but in addition the sediments are well described 

 and such topics as the physiography, {he local mineralogy, etc. 

 receive adequate treatment. The work of former investigators is 

 considered and a great amount of new material introduced. It is, 

 in fact, a very complete geological hand-book of the region and, 

 together with the excellent detailed map which accompanies it, 

 will be found of great service to every visiting geologist. 



l. v. P. 



8. New Mineral Names. — A minute examination of the original 

 Manganocaxcite of Breithaupt by Breusing has confirmed the 

 results of Rammelsberg and Des Cloizeaux that it is a mixture of 

 a carbonate and a silicate. The author shows further, however, 

 that the silicate belongs to the trielinic system and has the 

 probable composition H 2 Mn 3 (Si0 3 ) 4 -f-H 2 0. For this manganese 

 silicate the name agnolite (agnolith) is proposed. It is related to 

 inesite, which, however, contains calcium and has a somewhat 

 different ratio. — Jahrb. Min., JBeil. Bd. xiii, 265. 



Manganosphjerite is a carbonate of iron and manganese not 

 far from the oligonite of Breithaupt. It is described by Busz 

 from the Louise mine near Horhausen, Westerwald, Germany. 

 The composition corresponds to 3.FeC0 3 *2MnC0 3 . It occurs in 

 globular aggregations and fibrous forms, filling cavities and 

 narrow cracks in basalt; hardness 4*5 to 5; specific gravity 3*63. 

 Jahrb. Min. ii, 129, 1901. 



Esmeraldaite is a hydrous iron sesqui oxide described by A. 

 S. Eakle from Esmeralda count} r , Nevada. It occurs in pod-shaped 

 masses of a coal-black color, surrounded by a yellowish brown 



