Hector.—On Earthquakes and Wave Phenomena. 39 
must not be expected that they can express the facts in a very reliable 
manner. 
The smaller diagram shows the results of exact observations obtained in 
this harbour, at the end of Brown’s wharf, during twenty-four hours after 
the phenomenon was first observed. 
The altitude of each wave, as compared with its amplitude or breadth, 
has not been ascertained, irrespective of the degree to which it was modified 
by the local form of the shore upon which it expended its energy ; and this 
element is absolutely necessary for the purpose of determining the distance 
at which it originated. Nevertheless, as compared with the ordinary effects 
of the tidal wave, we can form some conception of the gigantic force which 
must have influenced the ocean along the coast, when we find that the ebb 
and flow which these waves caused in most cases, appear to have exceeded 
the ordinary local rise and fall of the tide at the different localities. This 
leads me to expect that waves of such magnitude must have been observed 
at many points beyond this colony, such as the coast of Australia to the 
westward, and the Chatham Islands to the eastward ; and that we shall 
receive information from these and probably other localities which will 
enable us to determine, with tolerable exactness, the focus from which they 
originated.* 
An earthquake shock appears to have been felt throughout the colony, a 
few minutes before 10 o’clock on Monday morning, the 17th inst., of a 
character very different from the. local shocks to which we are accustomed 
in this place. From the appended record of telegraphic announcements, it 
appears to have occurred about three minutes earlier in the north-east, at 
Napier, than at Hokitika on the west coast of the Middle Island. N apier 
is situated in lat. 39° 29’ S., long. 176° 55’ E.; Hokitika, in lat. 42° 41’ S., 
long. 170° 59' E. This gives a horizontal distance of 402 miles, but as we 
do not know whether the wave was travelling from the east or the north- 
east, it is impossible to infer its velocity. 
The following table shows the times at which the shock is reported to 
have been felt in various parts of the colony :— 
* The following information appears to have escaped the notice of the journals in the 
colony ; it is an extract from “ Principles of Geology,” by Sir Chas. Lyell, 10th edition, 1868, 
Vol. II., p. 409 :—* Even in the present year (November, 1867) a submarine volcano has burst 
out in the South Pacific, at a point 1,200 geographical miles from New Zealand and 1,800 
miles from Australia, between two of the most easterly islands of the Samoa or Navigator’s 
Group, an archipelago where there had been no tradition of an eruption within the 
memory of man. The outburst was preceded by numerous shocks of earthquakes. Jets of 
mud and dense columns of volcanic sand and stones, rising 2,000 feet, and the fearful 
crash of masses of rock hurled upwards, and coming in collision with others which were 
falling, attested the great volume of ejected matter, which accumulated in the bed of the 
th t protrusion of a new volcano above its level.” 
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