150 Scientific Intelligence. 
of 120° 20’, with the planes 7-7, 1-4, 4- 34 44; and also a octahe- 
dral planes. The inclination of 1-4 on the — re Cleay- 
age is distinct parallel to the besa nd imperfect in si direction 
of the vertical prism I. Maskelyne aaa observed that the crystals 
are optically fs vxial, Hardness between that of apatite and feld- 
spar, or 5°5. Specific gravity 2°245, ste of tridymite (another 
form of silica) being 2° 3, and of quartz 2°6. An analysis afforded 
Maskelyne —SiO? 9 430, Fe?08 1:124, CaO 0°578, MgO 1°509 
100°641. It is ees as insoluble in a solution of carbonate of 
soda as quart 
Vom Rath oe examined the mineral and confirms the results 
of Maskelyne. He obtained for the specified gravity 2°247; and 
for = sors sarah SiO? 96°3, FeO 1:6, MgO 1:1=99°0. The 
presence of iron and magnesia is attributed to the presence of a 
Little oe onzite, 
+ Maskelyne that z found 7h Partsch in the eteatte of 
Steinbach (which closely resembles that of ‘Bretentad may 
have been asmanit 
5. Miner: cniatiek Beobachtungen V; von Dr. Atprecut 
Scuraur. 88 pp. 8vo. (From the 67th ‘hie of the pase 
of the k. k, Akad. der Wismenccls 1873. Wien.)—This memoir 
by the eminent crystallographer of Vienna, is an elaborate eee 
on the mineral species of the Brochantite group. It gives a full 
=e of the er ponlene” of the spevies, and of their chemi- 
and physica! relatio 
group, obtaining in his sa ast 
Si 0, Al 29°0, Ca 11:2, K 115, Na 87, Cl 9°1, 5 1-7=104" 
sodium) on the silicate of the lava. Microsommite occurs in hex- 
agonal prfsms, with pyramidal | er on the basal edges, an 
hiss 43° 40’ as the basal angle of the pyramid, Vom Ra rt en” 
the eruption of 1872, as pir as augite, hovibleddk: seer toe 
biotite, negra and magnet 
V th’s paper on the ctyitsltiention of leucite, _—— out 
that it is ae is. 008 is contained in Poggendorff’s alen Er- 
ganzungsband, vol. vi; and the same paper ieee ts of the co aepecliod 
forms of the Vesuvian augite and hornblende derived from su 
