PRESIDENTIAL ADDRESS IN SECTION 
(Geology and Paleontology). 
OSCILLATIONS OF THE EARTH’S SURFACE. 
By F. W. HUTTON, M.A., F.G.8., C.M.Z.S., 
Professor of Geology, Canterbury College, University of New Zealand. 
Tuar the surface of the earth has moved is, at the present day, 
a part of common knowledge. Every one knows that high 
mountains are built up of rocks which were once beneath the 
sea, and that coal-beds, now so deeply buried, were formed on 
the surface of the land. It is nearly, perhaps not quite, as well 
known that these movements are still going on, some parts of 
the world undergoing slow upheaval, others slow depression. It 
has, however, only lately been discovered that, in addition to 
these slow movements, comparatively rapid wave-like pulsations 
of the land take place in Europe, in Japan, and probably in other 
laces. 
‘ It appears probable that the earth’s crust is in a constant state 
of movement, some parts sinking, others rising. There may be 
portions which are in equilibrium and stationary, but probably 
these areas are small in comparison with those undergoing move- 
ment. Oscillation is the normal condition of the surface, 
immobility is the exception. Oscillations like these have doubt- 
less been going on through all geological time, although with 
varying intensity ; and the movements have sometimes continued 
so long in one direction that we find places which have been 
elevated five or six miles above the sea level, and we can also 
prove that in places depression went on to the extent of six— 
perhaps even eight or ten—amiles below the sea. 
Professor G. H. Darwin has calculated that, if the earth be 
as elastic as steel, a rise of one inch in the barometer over the 
whole of Australia would indicate an increase of pressure 
sufficient to depress the surface two or three inches, while the 
tides of the Atlantic might cause a rise and fall in the neigh- 
bouring land of five inches. To these changes may be due some 
of the quicker pulsations ; others are annual, and appear to be 
due to changes in temperature, while others are independent of 
all meteorological causes. 
The origin of these latter pulsations, as also of the slower 
oscillations in level, has not yet been satisfactorily explained, and 
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