A. R. Leeds—Contributions to Mineralogy. 23 
chloric acid, the silica being left behind in microscopic colorless 
scales. Iron reaction with microcosmic salt. With calcic 
chloride in spectroscope, the lithium band. Composition: 
; II. 
I Mean. Calculated. O ratio. 
Si0, 36°03 35°84 35°99 87°45 19°195 6 
Ai,O, 9°19 9°85 9°52 14-27 "436 t 
FeO; 5°48 5°21 5°35 } 1°605 
Fe 0°94 a | 1°08 0°240 
MgO 33°05 32°93 32°94 33°30 13°176 
Na,O f : 
Li, ( 0°41 0°41 0°41 0°106 
H,O 14.66 14°53 14°60 14°98 12°978 4 
99°76 99°98 99°89 100-00 
Or for the bases and silica, O ratio= 19°56: 1919. This 
makes the mineral a hydrous unisilicate of the formula 
Il. Tale pseudomorphous after Pectolite. 
Occurs in the veins of calcite which traverse the trap rock in 
the vicinity of the Bergen Hill Tunnel, Hoboken, N. J. Struce- 
ture radiate, forming arrow-headed masses. Folia easily separ- 
able, brittle and varying in length from 1 to 50™™; smooth to 
acetic acid, and when collected by distillation gives with Nessler 
i ia. Partially decomposed 
ini rric 
oxides. Iron reaction with microcosmic salt. B.B. arkens, 
then becomes white, slightly exfoliates and fuses at the ends of 
thin splinters to a greyish-white enamel. Gives with cobalt 
solution a pink color on ignition. Composition: 
: ae Mean. O ratio 
SiO 60°54 60°57 60°55 32°293 
Mg6 26°46 26°67 26°56 10°624 
aie 1°06 0°98 1°02 
tt 0°70 0-74 0-72 
PS nO 0°55 0-76 0°65 10°401 
er 1°19 1°63 1.41 
20 9°52 9-09 9°30 
100°02 100°44 100°21 
