Admitting an action of this description to take place, it would then follow that. this extra liberation of gaseous material beneath the earth's crust would result in . an increased upward pressure from with

earth's crust to elevation. If we accept this as an explanation of the increased activity of a tremor indicator, then such an instrument may be regarded as a barometer, measuring by its motions the variations in the internal pressure of our planet.

is depressed. When the barometer falls, the load is removed from the area, which in virtue of its elasticity rises to its original position. This fall and rise of the ground completes a single pulsation. On the assumption that the earth is ex-in, and a tendency on the part of the tremely rigid, Mr. Darwin calculates that if the barometer rises an inch over an area like Australia, the load is sufficient to sink that continent two or three inches. The tides which twice a day load our shores cause the land to rise and fall in a similar manner. On the shores of the Atlantic, Mr. Darwin has calculated that this rise and fall of the land may be as much as five inches. By these risings and fallings of the land the inclination of the surface is so altered that the stile of a plummet suspended from a rigid support ought not always to hang over the same spot. There would be a deflection of the vertical.

The relief of external pressure and the increase of the internal pressure, it will be observed both tend in the same direction, namely, to an elevation of the earth's crust.

This explanation of the increased ac tivity of earth tremors, which is I believe due to M. di Rossi, is here only advanced as a speculation - more probable perhaps In short, calculation respecting the than many others. We know how a mass effects of loads of various descriptions of sulphur which has been fused in the which we know are by natural operations presence of water, in a closed boiler, gives continually being placed upon and re-up in the form of steam the occluded mois moved from the surface of various areas of the earth's surface, indicate that slow pulsatory movements of the earth's surface must be taking place, causing variations in inclination of one portion of the earth's crust relatively to another. That pulsatory motions of this description have repeatedly been observed it may be shown that there is but little doubt. The magnitude of these disturbances however is so great that we can hardly attribute their origin solely to the causes which have just been indicated. Rather than seeking an explanation from agencies exogenous to our earth we might perhaps with advantage appeal to the endogenous phenomena of our planet. When the barometer falls, which we have shown corresponds to an upward motion of the earth's crust, we know from the results of experiment that microseismic motions are particularly noticeable.

ture upon the relief of pressure. In a similar manner we see steam escaping from volcanic vents and cooling streams of lava. We also know how gas escapes from the pores and cavities in a seam of coal on the fall of the barometrical column. We also know that certain wells increase the height of their column under like conditions. The latter of these phenomena may be added to that which we have already mentioned, as a result consequent on diminution of atmospheric pressure, which, by its tendency to render an area of less weight, facilitates its rise.

The next question is as to whether we have any direct evidence of such heavings and sinkings in our earth's crust.

Although some of the proofs which are brought forward to show that slow pulsations like these are phenomena which have been repeatedly observed are unsatisfactory, taking them one with another they indicate that these pulsatory phenomena have a real existence.

As a pictorial illustration of what this really means, we may imagine ourselves to be residing on the loosely fitting lid of a large cauldron, the relief of the external Pendulums for instance which have pressure over which increases the activity been suspended for the purposes of seisof its internal ebullition; the jars atten-mometrical observations, have, both by dant on this ebullition are gradually prop-observers in Italy and Japan, been seen to agated from their endogenous source to have moved a short distance out from the exterior of our planet. This travelling and then back to their normal position. outwards would take place much in the This motion has simply taken place on same way that the vibrations consequent one side of their central position, and is to the rattle and jar of a large factory slow- not due to a swing. The character of ly spread themselves farther and farther these records is such that we might imagfrom the point where they were produced. |ine the soil on which the support of the

pendulum had rested to have been slowly | tilted and slowly lowered. They are the most marked on those pendulums provided with an index writing a record of its motions on a smoked-glass plate, which index is so arranged that it gives a multiplied representation of the relative motion between it and the earth. As motions of this sort might be possibly due to the action of moisture in the soil tilting the support of the pendulum, and to a variety of other accidental causes, we cannot insist on them as being certain indications that there are slow tips in the soil, but for the present allow them to remain as possible proofs of such phe


Evidences of displacements of the vertical which are more definite than the above are those made by Bertelli, Rossi, Count Malvasi, and other Italian observers, who, whilst recording earth tremors, have spent so much time in watching the vibrations of stiles of delicate pendulums by means of microscopes. As a result of these observations we are told that the point about which the stile of a pendulum oscillates is variable. These displacements take place in various azimuths, and they appear to be connected with changes of the barometer.

From this and from the fact that it is found that a number of different pendulums differently situated on the same area give similar evidence of these movements, it would hardly seem that this phenomena could be attributed to changes in temper ature, moisture, and the like. M. S. di Rossi lays stress on this point, especially in connection with his microseismograph, where there are a number of pendulums of unequal length which give indications of a like character. The directions in which these tips of the soil take place, which phenomena are noticeable in seismic as well as microseismic motions, Rossi states are related to the direction of certain lines of faulting.

Bubbles of delicate levels when examined by a microscope change their position with meteorological variations, but Rossi also tells us that they change their position, sometimes not to return for a long time, during a microseismic storm. Here again we have another phenomenon pointing to the fact that microseismic disturbances are the companions of slow alterations in level.*

Since my return to Japan in January, 1883, I may mention that I have commenced series of observations on earth tremors and earth pulsations, and on several occasions have observed very marked coincidences be

The more definite kinds of information which we have to bring forward, tending to prove the existence of earth pulsations too slow in period to be felt, are those which appear to be resultant phenomena of great earthquakes.

The phenomena that we are certain of in connection with earth vibrations, whether these vibrations are produced artificially by explosions of dynamite in bore-holes, or whether they are produced naturally by earthquakes, are, firstly, that a disturbance as it dies out at a given point often shows in the diagrams obtained by seismographs a decrease in period; and secondly, a similar decrease in the period of the disturbance takes place as the disturbance spreads.

As examples of these actions I will refer to the diagrams which I have given in a paper on the "Systematic Observation of Earthquakes" in Vol. IV. of the Transactions of the Seismological Society of Japan.

In a diagram of the disturbance of March 1, 1882, it seems that the vibrations at the commencement of the disturbance had a period of about three per second, near the middle of the disturbance the period is about 11, whilst near the end the period has decreased to '46. That is to say, the back and forth motion of the ground at the commencement of the earthquake was six times as great as it was near the end, when to make one complete oscillation it took between two and three seconds. Probably the period became still less, but was not recorded owing to the insensibility of the instruments to such slow motions.

We have not yet the means of comparing together diagrams of two or more earthquakes, one having been taken near to the origin and the other at a distance. The only comparisons which I have been enabled to make have been those of diagrams, taken of the same earthquake — one in Tokio and the other in Yokohama. As this base is only sixteen miles, and the earthquake may have originated at a distance of several hundreds of miles, comparisons like these can be of but little value.

The best diagrams to illustrate the point I wish to bring forward are those at the end of the paper just referred to.

tween barometrical depressions and these movements. Not only are these atmospheric changes accompanied with microseismic storms, but there are deflections in the stile of a pendulum, and changes in the position of the bulbs of delicate levels, which at such times can be seen with the naked eye to SURGE back and forth through a small range.

These are the results obtained at three stations in a straight line, but at different distances from the origin, of a disturbance produced by exploding a charge of dynamite in a bore-hole. A simple inspection of the diagrams shows that at the near station the disturbance consisted of back and forth motions which, compared with the same disturbance as recorded at a more distant station, were very rapid. Further, by examining the diagram of the motions, say at the near station, it is clearly evident that the period of the back and forth motion rapidly decreased as the motion died out.

Then illustrations are given, as examples out of a large series of other records, all showing like results.

and other Atlantic islands, the effects of the disturbance which created so much devastation in Portugal were also more or less severely felt as violent movements of the soil.

In other countries further distant, as, for instance, Great Britain, Holland, Norway and Sweden, and North America, although the records are numerous, the only phenomena which were particularly observed were the slow oscillations of the waters in lakes, ponds, canals, ete. In some instances the observers especially remarked that there was no motion in the


Pebbly Dam in Derbyshire, which is at large body of water covering some thirty acres, commenced to oscillate as a strong current from the south.

Loch Lomond rose and fell through about two and a half feet every five minutes, and all other lochs in Scotland seem to have been similarly agitated.

Although we must draw a distinction between earth waves and water waves, we A canal near Godalming flowed eight yet see that in these points they present a feet over the walk on the north side. striking likeness. Let us take, for exam- Coniston Water in Cumberland, which ple, any of the large earthquake waves is about five miles long, oscillated for which have originated off the coast of about five minutes, rising a yard up its South America, and then radiated out-shores. Near Durham a pond forty yards wards, until they spread across the Pacific, long and ten yards broad rose and fell to be recorded in Japan and other coun- about one foot for six or seven minutes. tries perhaps twenty-five hours afterwards, There were four or five ebbs and flows at a distance of nearly nine thousand per minute. miles from their origin. Near this origin they appeared as walls of water, which were seen rapidly advancing towards the coast. These have been from twenty to two hundred feet in height, and they succeeded each other at rapid intervals, until finally they died out as gentle waves. By the time these walls of water traversed the Pacific to, let us say, Japan, they broadened out to a swell so flat that it could not be detected on the smoothest water excepting along shore lines, where the water rose and fell like the tide. Instead of a wall of water sixty feet in height we have long flat undulations perhaps eight feet in height, but with a distance from crest to crest of more than one hundred and twenty miles.

If we turn to the effects of large earthquakes as exhibited on the land, I think that we shall find records of phenomena which are only to be explained on the assumption of an action having taken place analogous to that which takes place so often in the ocean, or an action similar to that exhibited by small earthquakes and artificially produced disturbances if greatly exaggerated.

At Shirbrun Castle in Oxfordshire, where the water in some moats and ponds was very carefully observed, it was noticed that the floods began gently, the velocity then increased, till at last with great impetuosity they reached their full height. Here the water remained for a little while, until the ebb commenced, at first gently but finally with great rapidity. At two extremities of a moat about one hundred yards long it was found that the sinkings and risings were almost simultaneous. The motions in the pond a short distance from the moat were also observed, and it was found that the risings and sinkings of the two did not agree.

Durings these motions there were several maxima.

These few examples of the motions of waters without any record of the motions of the ground at the time of the Lisbon earthquake must be taken as examples of a very large number of similar observations of which we have detailed accounts. As a remarkable instance of such phe- Like agitations it must also be rememnomena we may take the great earthquake | bered were perceived in North America of Lisbon on November 1, 1755. In and in Scandinavia, and if the lakes of Spain, northern Italy, the south of France other distant countries had been provided and Germany, northern Africa, Madeira | with sufficiently delicate apparatus, it is

not unlikely that like disturbances would have been recorded.

The only explanation for these nomena appears to be that the short quick vibrations which had ruined so many cities in Portugal had by the time that they had radiated to distant countries gradually become changed into long flat waves having a period of perhaps several minutes, and in countries like England these pulse like movements were too gentle to be perceived excepting in the effects produced by tipping up the beds of lakes and ponds. The phenomenon was not unlike that of a swell produced by a distant storm.

area, which may be regarded as an uncompleted effort in the establishment of an phe-earthquake or a volcano. The very fact that we know that volcanoes rising from deep oceans have in the first instance forced their way against a pressure of at least three or four tons to the square inch, indicates to us the existence of internal pressures tending to raise the crust of the earth, which pressures are infinitely greater than any of the pressures which we have upon the surface. of our earth produced by tides and variations in the barometrical column. If we follow the views of Mr. Mallet in considering that the pressures exerted on the crust of our earth may in volcanic regions be roughly estimated by the height of a column of lava in the volcanoes of such districts, we see that in the neighborhood of a volcano like Cotopaxi the upward pressures must have been many times greater than the pressures already mentioned-sea-level being taken as the line of hydrostatic equilibrium. The chief point, however, is that beneath the crust of our earth enormous pressures exist tending to cause eruption; and farther, that these are variable. Before a volcano bursts forth we should ex.

At Amsterdam and other towns chandeliers in churches were observed to swing. At Haarlem floods rose over the sides of tubs, and it is expressly mentioned that no motion was perceived in the ground.

At the Hague a tallow-chandler was surprised at the clashing noise made by his candles, and this the more so because no motion was felt under foot.

At Toplitz the pulsation of the ground appears to have manifested itself in effects upon the springs. The flow of the prin cipal spring was greatly increased. Be fore this increase it became turbid, and at one time stopped. Subsequently it be-pect that there would be in its vicinity an came clear, and flowed as usual, but the water was hotter and more strongly mineralized.

At one or two places, as, for instance, in Britain, slight earthquakes were experienced. These, however, were local, and in every probability were secondary disturbances produced by the pulsations causing ground in a critical state to give


In this earthquake I think, then, that we have a clear case of the production of pulsations in the soil that were too slow to be felt by ordinary observers.

upward bulging of the crust, and after its formation a fall. Farther, it is not diffi cult to conjecture other possible means by which such pressures may obtain relief.

Should these pressures then find relief without rupturing the surface, it is not difficult to imagine them as the originators of vast pulsations which may be recorded on the surface of the earth as wavelike motions of slow period similar to the motions in the outer area of a tract disturbed by a destructive earthquake.


That slow, undulatory motions changes in the vertical do occur in the crust of the earth, whatever may be their origin, we have numerous phenomena which certainly admit of explanation on such an assumption.

In Switzerland from time to time we hear of oscillations in the waters of lakes known under the name of Rhussen and Seiches. These, it may be remarked, are common to the lakes and inland seas of many countries.

Motions like these might be called slow earthquakes, and it does not seem unlikely that they are the resultants of all large disturbances. When they accompany a large earthquake like that of Lisbon, their cause is evident. But when we see the waters of lakes and ponds oscillating, the bulbs of levels disturbed, and the plummet line of pendulums displaced, the reason of these phenomena are not so apparent. It would seem possible that in some cases pulsations pro- Other examples of what may have been ducing these phenomena might have their a slow oscillating motion of the earth's origin beneath the oceans, or deep down crust are referred to by Mr. George Darbeneath the earth's crust. Perhaps, in-win in his report to the British Associa stead of commencing with the snap and jar of an earthquake, they may commence as a heaving or sinking of a considerable

tion in 1882. One of them was made by M. Magnus Nyrén at Pulkova, who, when engaged in levelling the axis of a tele

scope, observed spontaneous oscillations | pulse-like waves can, with these examples in the bulb of the level. before us, hardly be doubted. It must, however, be noted that they are of a different order to those phenomena which were so carefully sought for by the Darwins at Cambridge. JOHN MILNE.

This was on May 10 (April 28), 1877. The complete period was about twenty seconds, the amplitude being 15" and 2". One hour and fourteen minutes before this he observes that there had been a severe earthquake at Iquique, the distance to which in a straight line was ten thousand six hundred kilometres, and on an arc of a great circle twelve thousand five hundred kilometres.

On September 20 (8) in 1867, Mr Wagner had observed at Pulkova oscillations of 3", seven minutes before which there had been an earthquake at Malta.

On April 4 (March 23), 1868, an agita tion of the level had been observed by M. Gromadzki, five minutes before which there had been an earthquake in Turkes


Similar observations had been made twice before. These, however, had not been connected with any earthquakes, at least Mr. Darwin remarks with certainty.

Like phenomena are mentioned by M. S. di Rossi, in his "Meteorologica Endogena."

Thus on March 20, 1881, at 9 P.M., a watchmaker in Buenos Ayres observed that all his clocks oscillating north and south suddenly began to increase their amplitude, until some of them became twice as great as before. Similar observations were made in all the other shops. No motion of the earth was detected. Subsequently it was learnt that this corresponded with an earthquake in Santiago and Mendoza.

Another remarkable example illustrating the like phenomena are the observations which were made on December 21, 1860, by means of a barometer in San Francisco, which oscillated, with periods of rest, for half an hour. No shock was felt, nor is it likely that it was a local accident, as it could not be produced artificially. On the following day, however, a violent earthquake was experienced at Santiago.

This brings me to the end of the few important illustrations of the phenomena of earth pulsations which I have at ny disposal. With a little trouble I have no doubt that these might be greatly multiplied. As they stand, however, I think that they are quite sufficient to convince us of the existence of phenomena which hitherto have been almost entirely overlooked. That disturbances of the vertical are from time to time produced by long

Tokio, Japan.

From Chambers' Journal. UNCLAIMED MONEY.

THE " agony column" of our leading papers is invariably a source of considerable amusement to many people, by the extraordinary and generally romantic character of the notices to be found there, amongst which may be mentioned the curiosities of next of kin; and one and all naturally and justly arrive at the proper conclusion, that there is unquestionably a vast amount of property lying at the pres ent time unclaimed in England. Perhaps it is less difficult to find heirs, now that communication with the colonies is so rapid and constant; but for all that, the number of advertisements for next of kin proves that a difficulty still exists; and, in fact, few people are really aware how much unclaimed cash is still lying dormant, and how much has been appropri ated by government.

In novels, people are often made to pick up fortunes out of a chance newspaper, and the incident is dismissed by the reader as entirely growing out of the author's imagination. What ought to surprise us is, not that fortunes are sometimes thus obtained, but that millions of pounds sterling should be going about begging for an owner, and advertising themselves to an incredulous and indifferent public, who scarcely ever take the trouble to inquire about the large sums locked up in chancery, not to speak of unclaimed dividends, etc., still awaiting their proper owners. There are scores of people at present, belonging to a circle below that of the " upper ten," who have really fair grounds for expecting a change of fortune in the right direction some day, but they lack the necessary clue on which all their hopes turn. Others there are, both at home and abroad, who fancy they will in time come into something hand. some. Meanwhile, they trust to chance, without searching for themselves.

While it is not the writer's intention to weary the reader's patience with an array of dry statistical accounts, the mention of a few monetary items may have the effect

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