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EARTHQUAKE PHENOMENA IN TASMANTA. 
By Capr. Suortt, R.N. (Meteorological Observer.) 
[Read November 16, 1885. ] 
Since last November when I read a former paper on earth- 
quake shocks and tremors, and up to the present time there 
has been a considerable decrease both in the number and 
intensity of the shocks, excepting that of May 13th. 
From the table annexed with this paper, giving the time 
of occurrence, it will be observed, that at Gabo the shock is 
felt earlier than in Tasmania, also shocks have been felt 
farther inland on the continent of Australia, showing that 
the centre of disturbance during the past year, is to the north 
of the centre, marked in the Coloured Map, produced in my 
previous paper. The disturbance has been felt very severely 
at the Kent Group Lighthouse about a dozen panes of glass 
have been broken from the commencement. 
To strengthen the position I have taken in fixing the 
probable centre of disturbance. I will introduce the views of 
Professor Milne, of Japan, who recently visited Victoria and 
Tasmania, and published an article in the Melbourne Argus 
on the earth movements in Australia. Heis undoubtedly a 
sreat authority on Seismology, onaccount of Japan being always 
more or less in a state of disquietude from shocks and tremors, 
and his having had charge of the Seismological Department 
for some ten years, making a study of the Volcanic Phenomena, 
and his investigations have not been confined to actual disturb- 
ances, but also by experiments with dynamite discharges in 
the earth at various depths, by which he has gained much 
knowledge as to the rate of progression of shocks through 
different strata. 
The following are his conclusions on the disturbance affect- 
ing us :—“ From the various investigations which have been 
made, it appears that there is a line of weakness in the earth’s 
crust running parallel to the eastern coast of Tasmania. 
From time to time, whilst sinking to a state of equilibrium, 
this line gives way, first at one point and then at another. 
Each of these movements is announced as a series of tremors 
which now and then may be accompanied by one or more 
violent lurches. If this is a correct view to take, then, in a 
few years, it is possible that actual stability may be reached, 
and the earthquakes of Tasmania and Victoria become tradi- 
tion of the past. 
“ A second view is that the disturbances are directly con- 
nected with the capillary intrusion of sea-water to volcanic 
foci, consequent on which there are explosions and ruptures 
