ANNIVERSARY ADDRESS OF THE PRESIDENT. Ixy 
during the lapse of time, peculiarities arising in the fauna and flora of 
each, so that finally, when the deposits in the. surrounding tertiary seas 
were elevated above the water and became dry land, these islands 
constituted centres of terrestrial life, laying the foundation for the 
peculiarities now observable in different parts of Australia, though in 
equal latitudes and possessing similar climates. 
However imperfect, from the present state of our knowledge, every 
attempt to take a general view of the geological structure of Australia 
must necessarily be, this grouping together of observations by Mr. 
Beete Jukes is highly valuable, especially as, from his personal in- 
spection of several parts of the coast, he could the more readily seize 
resemblances and differences in rock masses which those accustomed 
to geological researches in the field know so well how to appreciate. 
It is by this gathering together of existing information, however im- 
perfect it may be, that we possess a kind of base on which to work, 
and so long as we treat this as an hypothesis, which may take any 
direction, to be even totally changed, should the gradual development 
of facts require it, no impediment to the progress of our knowledge is 
presented, but on the contrary much assistance to it is afforded. 
With regard to the changes and modifications mineral masses 
may have suffered since they were accumulated, and after any move- 
ments they may have sustained, we have to consider deposits formed 
in water and now elevated into the atmosphere, and others formed in 
comparatively shallow seas, depressed to various depths, and even 
covered by masses of mineral matter subsequently spread over them, 
as also some accumulations of mimeral substances, such as many vol- 
canic products, deserts of blown sand, and others, formed im the air 
and afterwards depressed beneath the waters. 
We have first to notice changes produced in the coal deposits of 
Eastern Virginia, and pointed out by Mr. Lyell. After describing the 
character of the coal itself, the difference of its layers, and the beau- 
tiful manner in which its vegetable structure, examined by Dr. 
Hooker, is partially preserved, he shows that this coal in its che- 
mical composition resembles that of the old paleeozoic rocks of 
Europe and of North America. “Analyses of specimens taken from 
three different localities (Clover Hill, Blackheath, and Deep-run) 
give carbon from 76°49 to 82:90 per cent. ; hydrogen from 4:08 to 
5°23; oxygen and nitrogen, taken together, ‘from 5°97 to 8-41 ; ; and 
ashes, or foreign matter, from 6°36 to 9°87. Thus we see that the 
changes from woody fibre to the coal, commonly termed bituminous, 
have been as great, as regards the loss of oxygen and hydrogen, com- 
bined with the requisite proportion of carbon, as those in the more 
ancient deposits, so that the conditions for such changes have been 
similar in both.cases. Although we now know that changes, even 
amounting to those required for the production of anthracite, are to» 
be observed in the vegetable matter in still more modern rocks, yet 
the quality of the coal in the Eastern Virginia coal-field is one of 
value theoretically, and important practically, as it forms an addi- 
tional instance to those already known of excellent workable coal being 
found otherwise than in the paleeozoic deposits. 
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