106 Sedimentary 'Formations 
In examining the gold alluvia at a variety of shafts about Gul- 
gong, Home Kule, and other places in the county of Phillip, I 
was struck by three prominent circumstances which have bearings 
upon the present and future of that region: 
1. No shaft is, so far as I learned, deeper than 200 feet, 
2. The gravels of the alluvia were composed of pebbles and 
fragments of rock common in the vicinity—derived from 
Carboniferous and underlying strata, with occasional 
fossils. 
JJ. The quartz pebbles were in some cases perfectly rounded; 
in others the quartz was in fragmentary lumps, as if 
recently broken from reefs. These did not appear to 
occur together. 
The conclusion I drew from the latter fact was that two periods 
of destruction and one of abrasion of underlying reefs had taken 
place at an early period of alluvial deposition. A fourth circum¬ 
stance might be commented on. In the deposits of the shafts a 
multitude of well worn abraded lumps of jasper, silicificd fossil 
wood, and semi-opal of various tints and clutlcedonie interchanges, 
in some instances themselves decomposing so as to exhibit this 
fibres of the wood from which they had been formed by transmu¬ 
tation, arrested attention, and showed that either an older series 
of Carboniferous rocks had suffered such changes, or the beds of 
the series which now exhibits itself in various outliers had under¬ 
gone the process. Mr. Lowe, of* Go ore e, has made a most ex¬ 
tensive collection of these altered fragments, in Which are many 
very beautiful specimens. It will probably never be rivalled, as 
he collected them from time to time as they were disinterred by 
the diggers. A great number also were coated with a shining 
transparent envelope of what I believe to be a deposit from 
silicificd water. Elsewhere (‘ ; Trmis. Roy. Soc. JS T .S. W., 1 1870, p. 
11) I have dwelt upon this; and it also attracted the attention 
of Professor Thomson and Mr* Norman Taylor. These deposits 
are frequently covered by a great thickness of basalt, upon which 
frequently lies a more recent drift partly derived from older 
drifts. The colours of the alluvia, now long exposed, rival in 
some degree those poikilitic hues which distinguish the west end 
of the Isle of Wight. 
A drift of local kind also occurs over largo areas in Manccro 
in the neighbourhood of the auriferous strata, as also in New 
England over the country of the tin-mines, which exhibits the 
same sort of alluvia as the gold-fields, and in which also gold 
occurs. In 1851-8, when I discovered the first tin in the 
Colony, it was generally in association with gold and gems. 
Messrs. Ulrich, Wilkinson, and Liversidge have since that time 
made local explorations both in the alluvia and in the beds from 
which they have been derived. There are deposits of opals 
