Howitt to Fison 21 November 1879

Transcription - Page 4

is a Basalt of the usual character
where olivine (the pale olive green
coloured minereal visible in it) predominates.
The other is a compound of plagioclase
felspar and Hornblende. The Basalt
is modern - of Tertiary age - but
the other rock may be either [modern - crossed out] volcanic
(Tertiary) or plutonic to use the
old terms (in the latter case of any
Pretertiary age) If of Tertiary age it will
be an Andesite, of Pretertiary age
it will be a Hornblende porphyrite.
I shall examine the other samples carefully
when I have time. More of these igneous
rocks will be very acceptable. Pieces about
1 1/2 inch cube broken from the interior
of a block - and thus [??] and undecomposed
are quite large enough for my purposes
By the Bye are you likely to visit the
Sydney exhibition? I ask because there is
to be a geological conference there in March
next and if you were likely to be in Sydney
I think it would determine one to attend.
My wife reminded me of this this morning
and said "give my compliments to Mr Fison
and say he ought to go."
Yours faithfully
A W Howitt