sed that the port was being
attacked, and the troops were put under arms.

2. At Singapore, distant 522 miles, two steamers were dispatched to
look out for the vessel which was supposed to be firing guns as
signals of distress.

3. At Bankok, in Siam, distant 1,413 miles, the report was heard on
the 27th; as also at Labuan, in Borneo, distant 1,037 miles.

4. At places in the Philippine Islands, distant about 1,450 miles,
detonations were heard on the 27th, at the time of the eruption.

The above places lie northwards of Krakatoa. In the opposite direction,
we have the following examples:--

5. At Perth, in Western Australia, distant 1,092 miles, sounds as
of guns firing at sea were heard; and at the Victorian Plains,
distant about 1,700 miles, similar sounds were heard.

6. In South Australia, at Alice's Springs, Undoolga, and other
places at distances of over 2,000 miles, the sounds of the eruption
were also heard.

7. In a westerly direction at Dutch Bay, Ceylon, distant 2,058
miles, the sounds were heard between 7 a.m. and 10 a.m. on the
morning of the 27th of August.

8. Lastly, at the Chagos Islands, distant 2,267 miles, the
detonations were audible between 10 and 11 a.m. of the same day.

Some of the above distances are so great that we may fail to realise
them; but they will be more easily appreciated, perhaps, if we change
the localities to our own side of the globe, and take two or three cases
with similar distances. Then, if the eruption had taken place amongst
the volcanoes of the Canaries, the detonations would have been heard at
Gibraltar, at Lisbon, at Portsmouth, Southampton, Cork, and probably at
Dublin and Liverpool; or, again, supposing the eruption had taken place
on the coast of Iceland, the report would have been heard all over the
western and northern coasts of the British Isles, as well as at
Amsterdam and the Hague. The enormous distance to which the sound
travelled in the case of Krakatoa was greatly due to the fact that the
explosions took place at the surface of the sea, and the sound was
carried along that surface uninterruptedly to the localities recorded; a
range of mountains intervening would have cut off the sound-wave at a
comparatively short distance from its source.

(3) _Oceanic Waves._--As may be supposed, the eruption gave rise to
great agitation of the ocean waters with variou