42 Transactions. 



confer a great beuefit to the coimtry, when we reflect on the great ad- 

 vantages the Province derived from the previous elevation of land, as large 

 tracts of the most valuable land were rendered available, which could 

 not otherwise have been drained without a very large expenditure of 

 capital. 



Third Communication on the same Suoject. 

 [Eead 12th October, 1868.] 

 In America there appear to have been two distinct shocks of great 

 magnitude, although smaller ones were felt at frequent intervals between 

 the 13th and 16th, as was the case in New Zealand. The first great shock 

 was experienced in Peru at 5 p.m. on the 13th of August, which time corre- 

 sponds in WelKngton vvith 9.30 a.m. on the morning of Fi-iday, the 14th. This 

 shock is described as coming from the south and west, and there is no doubt 

 that it was the result of a great submarine eruption at a considerable dis- 

 tance from the coast, as within a short time it was followed by three 

 ocean waves, which destroyed the towns along the coast of Peru for a dis- 

 tance of 1,000 miles, betv^een lat. 12° and 23° S. There is no reason to 

 doubt that it was the westerly propagation of the same three waves the first 

 of which reached New Zealand at 2.30 on the Saturday morning, having 

 traversed the width of the South Pacific Ocean (over 6,000 miles) in seven- 

 teen hours, giving an apparent average velocity of six miles per minute. 

 This agrees with the velocity formerly calculated for the wave from the 

 difference between the time at which it broke on the Chatham Islands and 

 the Australian coasts. A wave having its origin a few hundred miles from 

 the coast of Peru, say in lat. 25° S., as appears to have been the case in 

 this instance, would reach the Australian seas by the shortest route, follow- 

 ing what is termed a great circle, and would appear to reach us, not from 

 the north-east, as might be expected, but from the south-east ; the reason 

 of which can be readily understood by examining a globe. The force which 

 originated such a wave must have been tremendous, and there is no instance 

 on record in history of any earthquake v/ave of equal extent and magnitude. 

 The second calamitous event, as far as we yet know, only affected the Pro- 

 vince of Ecuador, v,^here, at 1.20 on the morning of the 16th, or at 6,10 on 

 the evening of Sunday, the 16th, in Wellington, a tremendous earthquake 

 shock passed sloioly from east to west, devastating the districts lying 

 on the western slopes of the Andes, between the Equator and lat. 5° S. 

 There is no reason to suppose that this shock, although its direction was the 

 same, had any connection with the shock which was experienced in New 

 Zealand on the following morning of Monday, the l7th, at 9.56 ; but it is 

 interesting to find that at that particular period the cause which gave rise 

 to earthquakes was in activity at wide distances apart on the earth's surface, 



