a | oe 
Second Supplement ta Dana’s Mineralogy. 209 
295}.—Haidinger has shown that the crystallization of Pennine is 
saree (Pogg., xcv, 620); he found for the refraction of the extraordinary ray 
1575, of the pee 1-576, Angle of the rhombehedron by measurement 67° 24’. 
Prrorsxitg [p. 345]—This mineral occurs in the valley of Zermatt, Switzerland, 
low, orange yellow, sometimes reddish brown; semi-transparent, and thin fragments 
sometimes transparent. von or —— white, A druse of minute transparent 
cubes observed on one specim ‘G=t087—$09 9. H=5°5. Attacked by hot 
muriatic acid and partiall Gaeak not acted on by prs acid ; sulphuric acid at 
P 
cig C. deco a jo it bes sinks dissolving the titanic acid and forming sulphate of 
Mea analyses: titanic acid 59°23, lime a 92, protoxyd of iron 1 8 
=100- ”. affording. the constitutio Os ti. The other minerals of this loc ocality ar 
garnet, idocrase, ham sa chlorite, ripidolite, serpentine, sphene, zircon, corundum 
rutile, magnetic nil 
The planes of th a dnjetile-e of Perofskite from the Urals, vey “i be 3-2 and A 
are, according to Kokscharov (Min. Russl., 1854, i, 199), 2-2 
as Pha ee eee, [p. cea bares of Lunnite from smtmee by Dr, Hed- 
[4], x 
B oo-73 Ms a 13 H 851 mixed aay 0'48=99°85 
consists of aggregated congeries of omgey spheres; G.=4 
The presence of a treat be selenium in thts 0 re from Rhelnbreitenbach has been 
ed by Bédeker (Ann. d. Ch. u. P Pharm., xciy, 356). He obtained one-sixth 
grm. from 50 grammes of the ore. 
Pragionite aga 5).—A crystal from Wolfsberg, beige the planes 0, 2, ii, 
and another of O, 2, are figured by Kenngott (Min. Not., No. 16). 
Prantxom [p. 12].—Loe. at Pt. Orford, California, Am. J. Sci. [2], xx, 79. 
Potyuauire [p, 377].—An coma by Dr. G. Jenszch pes ” alga of Prof. 
Hq. , , of a speeimen that came from ier, and is now in the museum of the 
Berlin Academy, afforded, on  ealculating om the results (Posi xeiv, 17 5): a 
Ca MgS xk 8 a. hh. Pe. Mae 
4411 1978 95:37 169 024 O11 101 039 002 616=9938, 
Proving that this dark red mineral from Vic is Polyhalite. 
‘ PREHNITOID, gg ewe: (Oefy. Akad. Forh, eee Pe go! aPumasges ag ro 
umnar. Pale gree ae vitreous. H.=17. fuses easily 
white cme acting like prehnite. Mean of 5 ae 
a Na K Mg Fe Mn ign, 
5600 2245 T79 eta ‘046 O86 4101 O18  104=99°36 
Oxygen 29:08 1049 921 958. 008 014 022 005 
Oxygen h ration for R, #, Si, 5-28 : 10-49 : 29°08=1: 2: rae Si+Al2 Sis, 
the oxygen ae of 8, # and dag: 2, we vite ds aN tie aagien Bak 
pred Siz, o Saad precisely (Re +8) toe in Seen 
umene, the oryee n ratio of the protoxyds in the Is 
ad 1 tata at i: 
J. 45 in his deduction res 
wore ee in the formulas of ate wise kaon 4 the 
complete analysis ‘de difference : 
formula o f barytes is Teo, 808. so he writes for prosopite te CaF, Al Fs, H. The 
P vnvalve the extraordinary supposition that Al and 8 are isomorphous. 
Mouruitz [p. 400],—Loe, Phoenixville, Pa, Smith, Am. J. Sci., xx, 2 
up Sxnins, Vol. XXI, No, 62, March, 1856. °7 
