WILL NEW ZEALAND BE AFFECTED?

Press, Volume LXII, Issue 12483, 20 April 1906, Page 8

WILL NEW ZEALAND BE AFFECTED?

' DR. C. COLERIDGE-FARR INTERVIEWED. A repoiter called upon I>r. C. Cole-ridge-Farr at Canterbury College yesterday morning, and when that gentleman hoard the news he ivas quite horrified. "It ie extraordinary—dreadful," he said. "But, ,, he added. "I don't think there is any cau.se for serious alarm here. Xo doubt we shall get a record of the shock here. I -will go to the Magnetic Observatory this afternoon and develop the recordi-. An earthquake usually indicates the slip of a fault, and it may Lt? succeeded l>3 , other smaller dips. Hut the fall having settled down is not likely to again. "We so continually have small slips here that it is extremely unlikely that we shall have a large one. If we went for some time without small slips wo might get something bad. If tlie catastrophe at San Francisco is as Iwul as you say, we may yet get a wave. But so far as 1 know we are not in the line of fault." AT THE OBSERVATORY. The Pressman again Dr. Farr at the Magnetic Observatory in the I afternoon. "I have developed the films, and we liave a record, " isaid the ! Doctor. •"Our instrument was first affected at about two o'clock thi- morni ing, and the earthquake must have begun from half an hour to aa hour, before that in San Francisco. According to our record the tremor must have lasted four hours. By the bye, there must have been a povere earthquake somewhere last Saturday. I don't know where it was. but we have a clear record of it. It miast have boon pretty bad." t " According to the time at which wo began to record the earthquake, jt must have started between four and fivo o'clock in the morning in San Francisco on the 18th inst., which would correspond to about 1 a.m. on the 19th hero," the Doctor continued. " Earthquakes make their effect ielt throughout the oru-t of the earth, and no doubt, on theoretical principles, every seiftnograph in tho world has received a record ot the San Franciivo earthquake, though, on practical

grounds, I should not like to swear to tne fact." HOW THE EARTHQUAKES ARE HfcCORDi^D. The instrument which records earth .tremors is known as tho Milne horizon- j tal pendulum seismograph. Tho. re-j porter saw the instrument at the Mag- ■ nctic Observatory. Though it is, in appearance, quite unlike a owing gate, it is-built on the principle of a swing gate. There Ls a light aluminium bcom, threw feet long, pivoted on a point. At the lurther end is a rectangular paper plate. Through a .-lit on this plate light is reflected on to a sensitive paper linn, wliich revolves by clock-work at tho rate of (50 millimetres per hour, night aiKl day. Wheuever an earth tremor occurs *it causes tho boom to swing, and the motions of tho boom aro photograplied by the reflected light on to the sensitive him. Under normal eircurmtancfs the point at the end of the boom in connection with the sensitive film traces a firm straight line oil tho him, but when tho boom sways the line break:, and blames serrated. Ihns an indication of the violence and duration of every earth tremor is obtained. Tho seismograph at the Observatory here runs duo north and south. X Un\o\vs therefore, that it tremor running duo north and south would bo m the axis of tiie boom, and would cause no deflection. A Uzjaor duo north and south would , consequently not bo recorded. Similarly a scMsmo-siaph placed duo oast and west would not record a tremor running duo emu and west. But tremors running either due north and south or duo east ij;,d west aro of such extremely rare occasion that they may bo treated as iic'gligcable quantities. Every observatory forwards its records to Mr Milne, secretary to the Seismological Committee of the British Association, and tin*** are. tabulated, so that the direction and speed of tho wave throughout, the earth's crust can bo ascertained. It takes between half an hour and an hour for a tremor to travel from on© extremity of tho earth to the other. THE SIGNIFICANCE OF EARTHQUAKES. Speaking of earthquakes air.d magnetic effects, Dr. Fair said there was considerable suspicion that there were magnetic effects duo to earthquakes. Some magnetic magma or masses are disturbed by tho tremors and their magnetic properties aro altered. 'This was tho case in the Cheviot earthquake, " Dr. Farr observed. "wheal tho magnetograps here showed considerable fluctuations." Dr. Farr was asked whether there was any scientific means of ascertaining tlio frequency of earthquakes. "Wo know of no periodicity," Dr. Farr replied, "but, of course, that does not provo that there is n»t one. On the oontrary, it is quito possible that there may bo one, but so far it lias not been ascertained." THE EARTH SLOWLY DYING. As to the oaiii&> of eartinquakes, Dr. Farr stated that they were consequent upon tho earth's loss of internal heat. Thio popular conception of the doctrine cf tho conservation of energy is that the amount of energy in the "world," meaning tho earth, never alters. "The truth-is that no energy is over lost in the universe," Dr. Farr said. "The earth does lose energy, and i« ever conr traoting, or shrinking, as a result. A time will come when/tho earth, will ho a cold, inert mats', ■with no animate life fcpcm, <t. Tho eartii is sfowfy dying, an.d every shook of earthquake is a step towards the ultimate extinotion of animal and vegetable life.. The rate of the loss of energy depends uLfaimabeiV upon the- rate of the Ices of heat. It is not possible to state what that rate is. Lord Kelvin mado an attempt, and deaueed therefrom the time since the earth was red-Jhot ajid. the duration of andmal ana vegetable life. But his argument was fallacious. Ho thought he had provided far ewry source of energy, hut he reckoned without Radium. The discovery of Radium and its properties has extended j the age of the earthy imeasuraWy, a.nd the old dispute between gecfrcgists and tho physicists (has been solved in favour of the former—so far as our present scientific knowledge, enables us to epeak. It is impossible for us to say when life will no longer be possible on this planet." NOT AX EXTRAORDINARY CONVULSION*. "We may get an increase of thermal action here as a result of the earthquake in Sojii Francisco, *'' Dr. Fair continued. "But as I told you this morning, I do not think we shall get any serious convulsion. I fancy the- earthqua kt> at San Francisco ds •not to be ! described as a very groat one. The record we have of it does not indicate thai- j it was. It 'happened to ita-ke place right j midc-r San Francisco, and , ko a great deal of damage has resulted. But I have often rccardsd qaiii!te as violent earthquakes. Just before the eruption of Mont Pelee there was an.-enormous earthquake in Central America. It did a great deal of diamage, though we heard very little of it here because it did <niot take place under a city like San Francisco. By tihe hyo, just recently the activity of Mont Pelee was renewed, anid as we have recently heard, Vesuvius has been very active. Al-' though the complete casual links cannot lie made cut, dlfc is very probable that there fa a α-elatioii between these eruptions and the present earthquake."