UNUSUAL TOURMALINE-ALBITE ROCK FROM ENOGGERA. 55 
has frequently taken place where the former is a basic rock, 
such transfer was not admitted in the case of granitic intru- 
sions.? Allport, as early as 1876, in discussing the altered 
Cornish slates, pointed out that of the minerals of the granite 
“schorl, two varieties of mica, quartz, and felspar,” 
“felspar is the only one absent from the altered slates.’’!° 
He was obviously unaware of the tourmaline-albite rock later 
described by Flett. 
In 1887 Rosenbusch," as a result of his work on contact 
phenomena in the Vosges, decided that nothing except a little 
boric acid had actually been added to the schists. In 188i 
G. W. Hawes,!? in describing the contact phenomena of the 
Albany granite, concluded that the addition of soda to the 
invaded strata ““may be regarded as certain.” In 1886 
Bonney! pointed out that the differences between schists of 
regional metamorphism on the one hand and contact meta- 
morphism on the other lay “* chiefly in the presence of felspar ”’ 
in the former. 
In 1894 Hutchings“ emphasized the fact that soda was 
transferred from basic intrusions but not from acid, but as the 
result of further work he came to the conclusion, in the fol- 
lowing year, that soda almost certainly was introduced from 
granitic masses.}° 
The albitites of Tilley!® and many pegmatites also force 
one to the conclusion that albite is a mineral which may be 
formed as the result of pneumatolytic, hydatogenetic, or 
deuteric processes, not only in basic but also in acid rocks, 
and as such may be expected in the metamorphosed rocks 
about a granitic intrusion. 
Flett assumes that the albite in the Cornish rock has not 
been introduced by the granite, for he writes: ‘‘ The abundance 
of albite leads us to correlate these rocks with the felspar 
hornstones of the calc-flintas series, and they may represent 
® See especially Roth, Chemische Geologie, vol. iii, 1893. 
10Q.J.G.S., 1876, p. 408. 
"1 Die Steiger Schiefe und ihre Contact zone, 1877, p. 257. 
12 Amer. Jrnl. Sci., 1881, p. 28. 
13 Pres. Add. Q.J.G.S., 1886, p. 104. 
14 Geol. Mag., 1894, p. 74. 
15 Geol. Mag., 1895, p. 165. 
16 Proce. Roy. Soc. S. Aus., 1919, p. 334. 
