246 



NATURE 



[January 13, 1898 



RECENT SEISMOLOGY. 

 I, — Earth Movements which we feel. 



THE circumstances which led to the recent advances 

 in seismological science are closely connected with 

 an earthquake-like reformation in the policy of a foreign 

 country. The country referred to is Japan, and the story 

 of the changes it so suddenly effected is well known. 



To bring about the new conditions engineers, archi- 

 tects, doctors, lawyers, surveyors, literati generally, 

 together with representatives of a variety of trades, were 

 invited to the birth of a new regime. 



The engineers built their bridges, but found that they 

 were shaken down ; architects were disheartened that 

 their houses were unroofed and subjected to processes 

 of shattering ; doctors learned that seismic disturbances 

 might be followed by nervous prostration, tetanus and 

 erysipelas ; lawyers were perhaps perplexed when their 

 opinion was required respecting the ownership of super- 

 imposed properties ; the surveyors saw that the area of 

 a piece of ground was not necessarily a constant quantity, 

 and that gate-posts, on which bench-marks had been 

 placed, might change their position by hopping — in short, 

 one and all were impressed by the mobility of their 

 near surroundings, and were often alarmed by rude 

 awakenings. 



The result of this was that an unusually keen interest 

 was taken in all that pertained to earthquakes, and the 

 new-comers, one and all — by speech, writing, or by 

 special investigation — contributed to the advancement 

 of seismological knowledge. 



Amongst the many workers stationed in Tokio we 

 find the names of Verbeek, Wagener, Knipping, Chaplin, 

 Mendenhall, Ewing, Gray, Perry, Ayrton, West, 

 Alexander and Knott ; whilst amongst the Japanese, no 

 less enthusiastic than their new colleagues, we see the 

 names of Sekiya, Omori, Hattori, and many others. 

 Outside assistance came from Bissett and Talbot in 

 Yokohama, Fukushi in Sapporo, and a number of other 

 workers throughout Japan. 



At this time Tokio was in reality a city of many 

 inventions, all of which were for the purpose of obtain- 

 ing trustworthy information about earthquakes ; their 

 name was legion, and it is no exaggeration to say that 

 of seismographs, seismoscopes and seismometers, more 

 than one worked with at least fifty different devices. 



One great problem which presented itself was to 

 suspend a mass of material so that at the time of an 

 earthquake it should practically remain at rest. The 

 solution was first sought for in the bob of an ordinary 

 pendulum. It being supposed that greater stability 

 would l)e attained if the lengths of the pendulums were 

 increased, three enthusiasts, in order to obtain a support 

 from the roof timbers of their houses, cut holes through 

 two ceilings, and the bobs of long pendulums were even 

 to be seen in drawing-rooms. 



Inasmuch as it was found that whenever a heavy earth- 

 quake occurred these pendulums were caused to swing 

 in some instances so violently that apparatus in their 

 vicinity was wrecked, attempts were made to render 

 them dead-beat and next astatic, and a series of experi- 

 ments were started which it would require pages to 

 describe. 



Following ordinary pendulums came horizontal pendu- 

 lums, combinations of ordinary and inverted pendulums, 

 rolling sphere and cylinder seismographs, ball and plate 

 seismographs, parallel motion seismographs, and such a 

 multitude of devices — not only for recor.ding earthquakes, 

 but also for timing them — that about 1883 it was decided 

 to hold a public exhibition of earthquake apparatus. 

 This was held in Uyeno Park ; it lasted three days, and 

 people flocked in such numbers to see the exhibits, that 

 police assistance was called in, and the sight-seers were 

 admitted in batches of about fifty. 



NO. 1472, VOL. 57] 



Although in Japan, as a whole, there are on the 

 average two or three earthquakes per day, whilst at 

 many stations fifty to eighty shocks may be recorded 

 during a year, because the disturbances came at un- 

 expected times and from unexpected quarters, the 

 appetite of the Tokio seismologists was so far from being 

 satisfied that a series of experiments, which extended 

 over several years, were inaugurated on artificially 

 produced earthquakes. 



The shakings were obtained at first by the fall, from 

 heights up to about thirty feet, of a ball approaching a 

 ton in weight, and subsequently by the explosion of 

 charges of dynamite and gunpowder in boreholes. 



The resulting vibrations — longitudinal, transverse, and 

 vertical — were recorded at a series of stations so arranged 

 in electrical connection that the time of any vibration 

 could be noted to within a small fraction of a second. 



Spare time was occupied in analysing earthquake 

 registers and the carrying out of seismic surveys. The 

 first of these was on an area of about nine acres, the 

 next extended over the city of Tokio, whilst the last 

 embraced a district some 500 miles in length, extending 

 from the capital to the northern island. 



In the first of these surveys a number of similar 

 seismographs, one of which was in a pit, were connected 

 together in the same manner that instruments had been 

 connected when studying the effects of artificially pro- 

 duced disturbances ; but with the latter, although a 

 certain number of seismometers and seismographs were 

 employed, the records were largely dependent upon 

 information received on post-cards respecting the time 

 at which a disturbance had occurred, and observations 

 respecting its duration, direction, and severity. 



This work, together with investigation on the volcanic 

 phenomena of Japan, the more or less mysterious sea 

 waves which occasionally inundated the coast, the sup- 

 posed relationship that might exist between magnetic, 

 electric, and seismic phenomena, the effect of earth- 

 quakes upon the lower animals, for studying which Prof. 

 Sekiya kept a pen of pheasants, and a variety of other 

 investigations formed interesting occupations for many. 



On February 22, 1880, seismic enthusiasm was brought 

 to a head by a very severe shaking, which gave to 

 Yokohama the appearance of a town which had been 

 bombarded. Taking advantage of the disturbed state 

 of mind common not only to those who were repairing 

 their roofs and chimneys, but to the whole community, 

 a meeting was called, and in less than sixty minutes the 

 Seismological Society of Japan, with its rules and 

 regulations, was established. Many paid their sub- 

 scriptions before they left the hall. 



One great incentive to the work was competition 

 between rival bodies, and many a time a member of the 

 new Society, because his seismogram of the last quake 

 was insignificant as compared with that obtained by a 

 neighbour, after bitter controversy returned home- 

 wards from a meeting with a sad heart. At first these 

 differences were regarded as the results of differences 

 in the adjustment or construction of the instruments 

 which had been employed, and it was not before sharp 

 battles had been fought that it was recognised that the 

 differences were due to differences in the localities of 

 installation. 



The feeling which at this time prevailed was not un- 

 like that which characterises many sportsmen who, in 

 the ordinary affairs of life, are everything that is admir- 

 able, but in the excitement of the field the desire to excel 

 exceeds all others. 



After seventeen years the seismic fever has abated, and 

 we say with the poet — 



" Haec olim meminisse juvabit.'" 



Now what was the good of all this expenditure of time 

 and money in the endeavour to trap the fleeting earth- 



