3880 Reports and Proceedings—Geological Society of London. 
been described, the origin of the present condition of the volcano 
was discussed in some detail, and the geological structure of the 
mountain and of the surrounding plain, as revealed by well-sections, 
was carefully considered. 
As the result of his observations, the author believes that he is 
able to define eight successive phases in the history of the volcano ; 
and the events which took place during these several periods, with 
the products of the eruption during each, were discussed in detail. 
The earliest certainly-recognized phase in the history of the moun- 
tain was distinguished by chronic activity, exhibited in outflows of 
lava and the ejection of scoria and ash. Possibly, however, a still 
earlier and paroxysmal stage is indicated by some of the phenomena 
described. Phase I]. was a period of inactivity and denudation, which 
was brought to aclose by the violent paroxysms of Phase III., followed 
by the chronic activity of Phase IV. Phase V. marks the return of 
a period of inactivity and denudation, which was again followed by 
the paroxysms of Phase VI. and the less violent outbursts of Phase 
VII., the last subsiding into the chronic activity which is the character- 
istic of Phase VIII., the modern period of the history of the volcano. 
The products of each of these periods of eruption were described in 
great detail. The eruptive phenomena which are illustrated by these 
studies of Somma and Vesuvius were then considered, together with 
the nature and result of the denudation which alternated with eruptive 
action in originating the present form of the mountain. ‘The paper 
concluded with a statement of fifty propositions on the subject of 
vulcanology which appear to the author to be established by the 
studies detailed in the paper. 
6. “Note on ‘Cone-in-Cone’ Structure.” By J. Young, Esq., F.G.8. 
This note was written with the object of calling the attention of 
the Geological Society to some very fine and remarkably interesting 
examples of the ‘‘ Cone-in-Cone” structure. 
The author, after referring to the views of previous authors on the 
origin of this structure, proceeded to describe the interesting examples 
of it which occur in the coalfields of Ayrshire and Renfrewshire. He 
pointed out that the structure is generally exhibited in bands over- 
lying beds of fossils. 
7. “A Geological Sketch of Quidong, Manaro, Australia.” By 
Alfred Morris, Esq., C.H., F.G.8. 
This district is situated about 250 miles §.S.E. from Sydney. The 
cliffs about the Bombala river are about 100 to 120 feet high, and 
formed of very dark limestone, crowded with fossils, chiefly Penta- 
merus. In the author’s opinion there has been great disturbance in 
this region, resulting in a complete change in the course of the river 
Bombala and a displacement of the shale. A mass of ferruginous 
sandstone has also been upheaved. ‘This, as well as the other rocks 
in the neighbourhood, contain Upper Silurian fossils. It appears 
to have been altered by heat. Pockets of galena and copper are 
occasionally found in the district, and there is a vein of haematite. 
Clay-slates occur as well as the above rocks, the cleavage being 
generally vertical or nearly so. 
