fA SHARP EARTHQUAKE.

New Zealand Herald, Volume XLIX, Issue 15003, 27 May 1912, Page 7

f A SHARP EARTHQUAKE.

SENSATION IN AUCKLAND. VERY LITTLE DAMAGE DONE. olT y>S NOVEL EXPERIENCE tajgST NOTABLE SHOCK for years. 'A SHARP earthquake, which caused much ■ excitement and some alarm was felt in Auckland at 6.5 p.m. yesterday, and apparently generally over the North Island at almost exactly the same time. Scarcely ;! n v damage seemed to be done. Much -alarm was caused, and probably some thousands of people ran out of doors in the foar that a catastrophe was imminent. There was porno warrant for their fright j„ one case, for a chimney in St. Stephen's Avenue, Parnell, was thrown down with a tremendous crash, and all the people in the neighbourhood were thoroughly startled. As /ar as could be ascertained last night no other incident so startling occurred. ' Owing to the limited hours during k-Mch telegraph officcs are open on Sundays only a few messages were received from other centres with regard to the disturbance. The shock was reported as having been light, at Rotorua, Ngaruawahia, and Hamilton, and fairly severe at Wellington. By post office time, it occurred at Auckland at 6.5, and at, Wellington at 6.4, but no other times were reported from telegraph stations last night. The Nature 0! the Shock. Earthquakes arc such extremely rare visitants to Auckland that the shock created a remarkable sensation. The experiences of Auckland people were extremely varied, and seemed to depend greatly upon local conditions, as well as upon the personal element, which counts so much in cases of emergency. Some who were upon solid earth missed the shock altogether; the faculty for observing such tremors seems to be quite absent in many people. Others who were outside were alarmed at tho noise of the shock, which was a very marked symptom of the disturbance, and was described by several observers as resembling the rushing of a strong wind. In most houses, tea was in progress, and trio first thing noticed was the rattling of windows and of crockery. The shock seemed to commence lightly with a rapid tuuugh slight vibration. It diminished in a few seconds, then rapidly increased again, till the oscillation was very noticeable. This died down again, and there followed a series of longer and slower weakening vibrations. The whole disturbance occupied about half a minute. Some of the Effects. While serious incidents were few, there were plenty of small manifestations of various kinds. The shock rang olaiashioned house bells hung upon springs in tome buildings, stopped several clocks, and left all sorts of pendant articles swinging. In many cases these remained swinging afterwards in a direction almost north and south, but as indications of the direction in which the shock travelled these were of slight value, as the waves which set them swinging were not necessarily moving in the same direction as the shock as a whole. Plaster was broken and fell from ceilings, and it is stated that in a few cases crockery was upset. A dock in the Royal Hotel had been lying • dormant for two or three days, bat tho pendulum was set swinging by the shock, much to the surprise of the waiters. Passengers Badly Scared. A peculiar effect of the earthquake was noticed at the Stanley Bay Wharf. A large number of passengers were waiting for a ferry "steamer, and were greatlj ' alarmed by feeling the wharf sway. It rocked and swung, and, to their somewhal disturbed imaginations, seemed about tc ** shut up like a concertina." Many oi them ran for tie shore, but the wharf is ' long, and the shock was over before thej had got very far, and they came back, very much agitated, and boarded the steamer. Some of the tramway men at , the Ponaonby barn were in a small corrugated iron enclosure at the time' of the shock, and the noise suggested that something had gone wrong with the wire® carrying several hundred volte, and they made haste to a safer place. r • A Scientist's Observations. Professor A. P. W. Thomas, of the Auckland University, was one of the most interested observers of the phenomenon. He told a reporter last night that his records of previous earthquakes were not immediately available, so that he could not give dates. But he was virtually sure that only three or four shocks of such • magnitude as yesterday's had occurred in Auckland during the past 30 years, and that it was many years since the city had experienced a shock at all. The fact that the shake was felt at Wellington a minute earlier than at Auckland gave no indication as to its origin, and at the time • there was far too little information available to enable one to reach any conclusion. Only by having a large number of exactly observed times can a chart be plotted out 80 as to give an indication of its source. The nature of the vibrations suggested, however, that the shock had travelled a long distance. It was almost certain that it had not started within New Zealand, though, in the absence of further information, it was possible. There was nothing about the shock to suggest that it was the result of a volcanic explosion.

The Causes of Earthquakes. Professor Thomas, speaking upon earthquakes generally, said that the most usual cause for earthquakes was the gradual loading of some part of the earth with material removed from another part by the action of rivers or other influences. The altered pressures set up strains in the earth's crust, and when at last it gave way a little under the strain, the sudden movement gave rise to the shock. Such earthquakes were called tectonic. The shrinkage of tho earth and the consequent wrinkling of the crust was another cause upon which a theory had been based, but leas stress was laid on it now than formerly. Professor Thomas added that ho had a seismograph, or instrument for recording earthquakes, but it was not set up. Phenomena of the kind were so extremely rare in Auckland that it was not worth While to keep it in commission.

Prospect of a Shaky Winter.

A well-known Auckland meteorologist, Mr. J. Stevenson, stated that the shock did not appear to have any connection with solar or lunar influences. Mr. StevenBon remarked upon the marked distinctness of the tremors which preceded the main shock, and said that the wave appeared to have come from the southward. He suggested that an earthquake period would probably occur during the winter months, but he did not anticipate any serious seismic disturbances in the Auckland province.