G. J. Brush on Sussexite. 241 
4 drop of dilute chlorhydric acid and afterwards dried, it as- 
sumes the red color, characteristic of boric acid, and thus shows 
_ that at least a trace of this acid is driven off with the water. 
In the forceps the mineral fuses in the flame of a candle (F.=2 
and B.B. in O. F. yields a black crystalline mass and colors 
the flame intensely yellowish-green. With borax and salt of 
bsohe gives a deep amethystine bead in O. F., which in 
. #., becomes colorless and transparent. With soda yields a 
green manganate 
pA iagment of the mineral moistened with sulphuric acid and 
‘eld in the flame of an ordinary Bunsen burner gave, when 0 
“rved through the spectroscope, the characteristic spectrum of 
boric acid. 
, The exceedingly simple composition of the mineral rendered 
"quantitative determination of the bases comparatively easy. 
~“ uneral being dissolved in chlorhydric acid, the excess of 
_ ; Mm Was driven off and the manganese was thrown down by 
bromine in the presence of an excess of acetate of soda as 
 ‘bydrated Sesquioxyd; this was re-dissolved and precipitated 
s ammonio~phosphate and weighed as pyro-phosphate.* The 
; ok 
Da petal of this admirable method for the estimation of manganese See 
: hy 3 ? 
Phil. Mag., IV, xvi, 197; and W. Gibbs, this Journal, II, xliv, 216. 
