I. PREVIOUS STUDIES & ISSUES既往研究とその課題

(1) Gregory Clancey, Earthquake Nation,2006.

  His arguments starts in the articles written by professors of the Technical College, lated Imperial College of Engineering. However, several foreign engineers already started scientific arguments and seismic observations.

・基本的には、1880年の地震学会創設と、1891年の濃尾地震への対応を、日本地震学の黎明ととらえており、1870年代の様子が分からない。

(2)  今村明恒、明治大正年間における本邦地震学の発達、地震（90）10、1929年。 

「其八年には内務省地理局の一課に於いて地震の記録を司ることゝなり、新に伊國パルミエーリ式の振子地震計も購入された。此庭から生れ出でた氣象臺が幾多の變遷を経て次第に發達し、遂に今日の盛況を見るに至るまでの間に於いて、地震に關する觀測並に統計の事業も之に伴って次第に發達して來たのであるが、併しながら其發達の基礎が、日本地震學會に依って築かれたことを否むことは出來ない。一方氣象臺の地震事業進歩に伴ひ、地方測候所も亦漸次に此方面にも注意を向けるやうになう、遂に今日に於けるが如く、地震の觀測網が隈なく全國を被ふやうになつのである。

・内務省による地震観測は明治8年からとしてよいか？

・パリミエリ式地震計が誰がどのようにして日本にもたらされたのか？その成果は？

(3) 矢島道子＋和田純夫編「はじめての地学・天文学史」ベレ出版、2004年。39頁、多様な現象の研究 

--1860年前後、イギリスにおけるマレットとホプキンズによる地震の発生理論が組み立てられたことを紹介し、「観測に使われた最初の感震器は、1856年にイタリア・ベズビオ火山の観測所に設置されたものです。発明者の名をとって、パルミエリ（注18）感震器（または地震計）と呼ばれています。地震の水平方向の揺れは、水銀を満たしたU字管に鉄の浮きを浮かべ、その浮きの動きで検出しました。上下方向の揺れは、ばねで支えられた錘の動きで検出しました。地実動の方向や強さ、継続時間は記録できましたが、まだ波の形を連続的に記録することはできませんでした。日本でも1874年に輸人され、観測に使われました」、さらに「地震動を連続的に記録することができる最初の地礎計を作ったのは、地震国・日本にやってきた御雇い外国人教師のユーイング（注19）でした。米日2年目の1880年に、振り子 を水平に近い位批に置けば、振り子の周期を長くできることに着11して、水平振り子を応 用した初めての地震計を製作して、記録をとるのに成功しました。ユーイングの地震計は、御雇い外国人教師として来日していたミルン（注20）やグレー（注21）も加わって何度かの改良が施され、上下動を観測できる地震計も付け加えたグレー・ ミルン・ユーイング地震計に発展しました 」と、実用的な地震計の開発までを述べている。

・地震と台風は日本にやってきた外国人科学技術者の最大の関心事であり、地震に関してはマレットとホプキンズの地震理論の紹介はユーイングやミルンによるとしてよいのか？

・パルミエリ地震計とユーイング・ミルンによって具体的にどのように改良されたのか分からない。

(4) 地震学会の初代会長として選出された山尾庸三のこと

・会長就任要請に対して、山尾はそれを断った。工部卿として公務多忙が表向きの理由だが、1873年の時点で工部省測量司が気象観測・地震観測を担うことを承認し、測量師長マクヴェインに対してその機器の購入と人員配置を任せた。しかし、1874年1月、内務卿の大久保利通の愚策を止められず、これは頓挫してしまい、内外関係者を大変落胆させてしまった。おめおめと山尾は会長職に収まるわけにはいかなかった。

II. Brunton's Argument of Earthquakeブラントンの議論

・日本の近代科学技術発展に大きな貢献をした人物であることは間違いなく、日本アジア協会創設時から科学部座長を務め、同協会論文集や「ジャパン・ウィークリー・メール」誌にエネルギッシュに科学技術関連論文を発表した。同時代のイギリス人若者と同じように徒弟制で実務を学び、夕方からは理論をギルド・スクールの夜学で熱心に学んだのであろう。

・歯に衣着せぬ物言いは多くの人物と衝突し、灯台建設を巡ってはマクヴェインとブランデルと、河川改修を巡ってはオランダ人技術者たちと、技術者教育に関してはヘンリー・ダイアーと反目した。ブラントンやマクヴェインの後のイギリス人技術者は徒弟制実務訓練ではなく大学教育を通して育成され、高度で広範な理論を学習した。それらを身に付けたエアトンやダイアーらと論争に太刀打ちできるはずはなく、帰国時には限界を感じていたのであろう。

(1) May 14, 1870, THE JAPAN WEEKLY MAIL

EARTHQUAKES

The frequency and severity of the shocks of Earthquakes which have been felt in Yokohama within the last week have caused serious apprehensions in the minds of many people, and all sorts of ingenious theories are afloat as to the cause and nature of these disturbances.

   It may not therefore be uninteresting to our readers if we give them, in a general way, so much as we know of what science has discovered in relation to Earthquakes, though it be not much, and not likely to allay the dread which must always surround such a mysterious and appalling action of nature's forces, or effectual in enabling them to avoid the dreadful consequences which sometimes follow these visitations.

先週横浜で感じられた地震の周期と強度は多くの人に重大な不安をもたらした。読者にとっては興味のないことかもしれないが、これに関連して科学がどのような発見をしているのか紹介したい。

   Accounts of the effects of the severest known Earthquakes have been regularly published since that which occurred in Calabria in 1783. But no deductions seem to have been made from them until 1858, when Mr. Robert Mallet, C.E., volunteered to proceed to Naples to examine into the Earthquake which almost destroyed the towns and a great part of the population of that Kingdon a year previously. He went out under the auspices of the Royal Society of London which reimbursed the expenses of the investigation; and the book which he published, giving the result of his researches, is the only one in the English language which, to our knowledge, can be looked upon as an authority on the subject. The principle on which he has grounded his deductions, and on which his whole theory rests is, in his own words, as follows.

1783年にカラブリアで発生した地震についての記録があるが、その後、1858年までなかった。その年、技師のロバート・マレット氏は地震を調査するためにナポリに赴いた。そこでは一年前に大地震が発生し、都市の大部分を破壊し、また多くの人命を奪った。彼は調査報告を出版し、彼の理論は以下の通りである。

   "There is every reason to consider it established that an Earthquake is simply the transit of a wave or waves of elastic compression in any direction, from vertically upwards to horizontally, in any azimuth through the crust and surface of the earth, from any centre of impulse or from more than one, and which may be attended with sound or tidal waves dependent upon the impulse, and upon circumstances of position as to sea and land."

   That is, when a disturbance occurs in the interior of the earth it gives an impulse to the substances immediately surrounding it, which impulse is transmitted to the surface in waves, the direction and the force of which can be calculated by the well known laws of elasticity.

「地震とは単純にいかなる方向への波の移動かあるいは弾性圧力の波である。垂直上方への、地球の地殻と表皮を通るあらゆる方向へ、」

   The cause of the disturbance is, Mr. Mallet says, "supposed to be due to a sudden Volcanic outburst or sudden upheaval or depression of a limited area, or the sudden fracture of bent or strained strata—or probably to the formation of steam, & c." But his investigations principally tend towards a discovery of the position, size & c., of the origin of the disturbance.

    To illustrate how this may be arrived at, we will suppose a shell to be exploded under water. The greatest disturbance on the surface will take place at a point vertically above the position of the explosion, and concentric waves will move directly away from this point, losing in velocity and power as they are distant from the centre. Some such action takes place in the case of an Earthquake, with the difference of course, that it deals with a solid instead of a liquid body, and different degrees of elasticity caused by the numerous formations in the earth's substance make irregularities, which, however, do not affect the general principle.

   The position of the origin is arrived at by noting the direction in which the waves travel, it being assumed that they travel outwards in every direction from what is termed the seismic vertical ; and its depth below the surface discovered can be by the direction of emergence of the shock at different points, or the angle with a horizontal line at which the wave of shock emerges from the earth.

   These are the principles on which Mr. Mallet set to work, and the result of his investigations at Naples was shortly as follows. By noting the severity and direction of the shock at various places, by observing the fissures in rocks and buildings, the position of overturned erections, alterations on the surface of the ground and other phenomena, he concluded that the origin of the Earthquake was about six miles below the surface of the earth.

   He was assured of the correctness of this conclusion from the fact that ho took the angle of emergence at twenty or thirty different places, all of which pointed to the same locality. The velocity of the wave varied from a thousand to five hundred feet per second, according to the distance it was from the " vertical." The rate of the movement of the wave particle, or what may be termed the sharpness of the shock, varied from twenty one to ninety feet per second. The first boundary or figure surrounding the "vertical" within which the shock was most severely felt, and where towns were completely prostrated, was 716 square miles in area.

   The second boundary within which there was a consider able destruction of edifices was 1685 square miles in area. The third, within which there was Assuring of walls and other indications of slight shock was 4,976 square miles ; and the fourth, within which the shock was distinctly felt, but no damage whatever done, 29,500 square miles. Out side of this there wore no indications of shock whatever. From the form of these figures and from the convergence of the wave paths to a certain area, from the nature of the sounds heard round the "vertical," and from tremulous movements felt in the same locality, it was deduced that the subterraneous cavity in which the disturbance took place was about nine miles long by about three miles high. If this theory is correct, and we know of no reason why it should not be accepted as such, there are several conclusions which may be drawn from it which will set at rest many fallacies on the subject.

   1st.—" An Earthquake, however great, is incapable of producing any permanent elevation or depression of the land whatever ; its functions of elevation and depression are limited solely to the sudden rise, and as immediate fall, of that limited portion of the surface through which the great wave is actually passing momentarily."

   2nd.—The sea wave, or what is known as a tidal wave, which has caused such destruction along the coasts of countries subject to Earthquakes is caused by the "vertical" being somewhere in the sea. The agitation in the bowels of the earth is transmitted vertically upwards to the surface of the Ocean, and thence horizontally in every direction in huge waves, as already explained.

   3rd. —The severity of the shock depends partly upon the distance from the "vertical" and partly upon the elasticity of the substance through which the shock is trans mitted. This is evident if we consider the rapidity of movement of the wave particles as the severity of the shock. The velocity of the wave of sound or verberation is one hundred times greater in iron than in water, and in the same way, the disturbance caused by an earthquake will be transmitted with more effect and rapidity through a rock or homogeneous structure than through a clay for mation. It is by this muans that we account for shocks being more severely felt in one place than another, whose distance apart could not cause the difference.

   In this country, in the beginning of September fifteen years ago, Yedo was visited by a severe succession of shocks which overturned a great part of the houses in the city, the falling timbers caught fire, and the whole place was rapidly reduced to a scene of desolation. Minor shocks were felt for several days previous to and subsequently to the larger one. At the same time Simoda was almost destroyed, but from a different cause ; a shock was felt there but it was not severe and no houses suffered from it. A quarter of an hour after the shock, however, a sea wave swept along the coast carrying destruction with it and nearly, reducing the whole town to ruins. At Oosima, and 1 75 miles to the South westward, the shock was only slightly felt and the wave did not reach there at all. At Hiogo there was no perceptible trace of it.

   The shock being so severely felt in Yedo, and not so severely in Simoda, would lead to the conclusion that its origin was at some place more distant from Simoda than from Yedo, and the fact of the sea wave having swept on to the coast in the neighbourhood of Simoda would lead to the inference that the origin of the " vertical " was in the sea. Such inferences are however perfectly futile as scientific conclusions, without more reliable data than we are possessed of.

   It would be interesting to know whether the shocks we are now experiencing proceed from the same origin as that which produced the last great earthquake, or whether another disturbed locality exists in our neighbourhood. By a series of properly conducted observations with appropriate instruments, we have no doubt information could be obtained, which though not entirely reliable as a warning, would still give us some idea of what to expect.

   It may not be out of place here to mention that together with the other meteorological instruments which are generally placed at lighthouses, it is intended to place seismometers of simple construction at each of the lighthouses on the Coast.

［解題］この論文において、ブラントンはイギリス技師のロバート・マレットの研究を通して、地震の正体を紹介している。灯台に地震計を設置することを提案している。

(2) Robert Malletロバート・マレットについて

Robert Mallet Founds the Science of Seismology, 1850 to 1858

   Between 1850 and 1858 Irish geophysicist and civil engineer Robert Mallet of Dublin founded the science of seismology in a series of four Report[s] of the Facts of Earthquake Phaenomena presented to the British Association for the Advancement of of Science. He also issued The Earthquake Catalogue of the British Association. Mallet coined the term "seismology" to describe the scientific study of earthquakes, and was also responsible for the terms "epicenter," "seismic focus" (the point at which an earthquake originates), "angle of emergence," "isoseismal line" (contour or line on a map bounding points of equal intensity for a particular earthquake), and "meizoseismal area" (area of maximum earthquake damage).

   "He produced an experimental seismograph in 1846. Important elements of his model, which was never actually used, were incorporated in the seismograph that Luigi Palmieri made in 1855. Between 1850 and 1861 Mallet set off explosions in different locations to determine the rate of travel of seismic waves in sand (825 feet per second), solid granite (1,665 feet per second) and quartzite (1,162 feet per second). According to A. Sieberg (1924), Mallet should be considered the founder of the physics of earthquakes. . . . Mallet presented his most important seismic results in four Report[s] to the British Association (1850, 1851, 1852-54, 1858) and in four editions of the Admiralty Manual of Scientific Enquiry (1849, 1851, 1859, 1871). Between them, they contain an extensive catalog-which he prepared and debated with his son, John W. Mallet- of 6,831 earthquakes reported between 1606 B.C. and A.D. 1858 and his seismic map of the world" (Dictionary of Scientific Biography).

Robert Mallet, (born June 3, 1810, Dublin, Ireland—died November 5, 1881, London, England), Irish geophysicist, civil engineer, and scientific investigator who is sometimes called the “father of seismology” for his work on earthquakes.

    He studied at Trinity College and in 1831 took charge of his father’s Victoria foundry, which he expanded into the dominant foundry in Ireland. At age 22 he was elected to the Royal Irish Academy and was also a member of the British Association for the Advancement of Science (now the British Science Association) and the Royal Geological Society of Ireland. He built an early form of seismograph and conducted some of the first controlled seismic explosions with his son John William Mallet in 1849. Following the deadly earthquake in Naples in 1857, he traveled to Italy and painstakingly analyzed the damage. His use of photography during this expedition was a remarkably early scientific use of the new technology, and his findings were published in an award-winning report, The First Principles of Observational Seismology. He is believed to have coined the terms seismology and epicentre.

Great Neapolitan Earthquake of 1857. The First Principles of Observational Seismology

As Developed in the Report to the Royal Society of London of the Expedition made by Command of the Society 

to Investigate the Circumstances of the Great Earthquake of December 1857.OF THE EXPEDITION MADE BY COMMAND OF THE SOCIETY INTO

by Robert Mallet, C.E. , F.R.S. , F.G.S., M.R.I.A.,

Published by the Authority and with the Aid of the Royal Society of London.

in Two Volumes, Chapman and Hall, London. 1862.

III. McVean's Attempt to Observe the Earthquake測量師長マクヴェインの試み

(1) Need of Observation地震観測の必要性

(2) Luiz Palmieriルイージ・パルミエリ

(3) Purchase of Instruments地震計の購入

(4) Setting up the Instrument at Yamato Yashiki大和屋敷観測所

IV. Constructive Art in Japan, by H. Henry Brunton. Transaction of Asiatic Society of Japan, Volume II. 1873-1874, pp.64*86.

  The accounts of Japan which at the present time are generally spread throughout Europe, are so exaggerated, that both the natural beautics and wealth of the country as well as its genuine condition and the progress which it has made, are greatly over - estimated by those who have not had an opportunity of visiting the country and of judging of them for themselves.

現在ヨーロッパに広がっている日本についての記述は誇張しすぎており、自然の美しさと国の富の両方、さらに、純粋な性質と進歩の状況はここに来たことのない人たちによって大げさに語られているだけだ。

   Every one, therefore, who comes to Japan is led to expect too much, and there are few who on arrival do not experience feelings of disappointment. And it is probable that nothing developes these feelings more fully than the absence of those artificial improvements which are generally met with in all civilised countries.

日本にやってくる人は誰で多くを期待しているが、到着してみるとそこには文明国に見られる人工の改善というものはなく、失望を経験しなかった人はほとんどいない。

 The dwellings of the people are of mean appearance, and are generally without ornament or adornment of any kind. They are built in it temporary and unsubstantial manner, and are to it great extent wanting in the comforts which are ordinary in all European houses.

人々の住まいは貧しい姿をしており、まったくなんの装飾も飾りもついていない。これらは仮設的に応急的に造られるにすぎない。さらに、ヨーロッパ人の住まいにあるような快適さはまったくもって存在しない。

   The streets in the principal towns, as well as the country roads, are rutted, uneven and perfectly untended; and although gravel is sometimes used, the roads are generally merely formed of the earth or clay through which they pass.

   There is almost an entire absence of drainage and the refuse water from the houses is allowed to spread itself over the streets. The rain water has no means of egress, and lies in pools until it has time to sink into the earth or is evaporated.

大きな町の通りでも、田舎の道でも、轍があり、平らではなく、でこぼこしている。場合によって砂利が敷いてあっても、道は土や粘土の形式となっている。

排水路はほとんどなく、家からの排水が道に流れ込む。雨水は道にあふれ、水たまりとなり、晴れると土にしみ込むか蒸発する。

   It is further impossible to repress a feeling of disappointment when we turn to the religious monuments of the country. The temples are stately, they are generally exquisitely ornamented, and are certainly built in a more stable and substantial manner than the other erections around them. But there is so great a sameness about them that it seems as if the original designer had made a groove so deep that all the intellectual power of the Japanese could not raise their architects out of it.

この国の宗教的記念碑に目をやっていると、そこでは私たちは失望の念を禁じ得ない。寺院は堂々とし、そこには絶妙な装飾が付いており、これらはより安定的な本格的な技法で建てられている。しかし、これらはほとんどよく似ており、最初の設計者がたよって日本では建築家を育ててこなかった。

   That earthquakes are prevalent throughout the whole of Japan is a fact which, in the minds of many, has affected the whole system of building in Japan, and has prevented the development of the native talent for construction. This is looked upon as sufficient reason for the absence of stone erections or buildings of solidity and durability. But if earthquakes have exercised this influence over the Japanese mind, the people have been influenced by false premises; as I think that to imagine that slight buildings, such as are seen here, at the best calculated to withstand an earthquake shock is an error of the most palpable kind.

日本中どこでも地震が多発し、多くの人の心の中に、建築システムに大きな影響を与え、そしてここの建設の能力の発展を妨げている。これは石造建築や固く耐久的な建築がない大きな理由となっている。しかし、もし地震が日本人の心の中にこのような影響を与えたとしたなら、人々は間違った前提に影響されてしまった。そこかしこで見られる軽微な建物が地震の衝撃に耐えうる最も方法であるとするのは、大きな誤りである。

   Now that foreigners have introduced a different system of building, the present Japanese have no hesitation in adopting it, and edifices of any size or material are now erected with their approval. No objection is ever made on account of earthquakes, and on these grounds I am of opinion that at all events the present race have not that dread of earthquakes which would lead them to eschew solid constructions, and we must beck at wine other source the reasons for the want of progress in the art of building.

現在、外国人たちは異なった建築システムを紹介し、日本人たちはそれを躊躇なく導入しようとしており、さまざまな材料と大きさの邸宅が彼らの合意の元に建てられている。地震に対して対抗策をとるでもなく、それに恐れおののいて逃げるだけでは、建築の発展はまったく望めない。

   The whole country is subject to earthquakes, and there is hardly an island or a province of Japan that has not at some time or other suffered from their effects. Through the courtesy of certain Japanese officials I have been put in possession of some information, which I have every reason to believe to be correct, regarding the destructive earthquakes which have occurred. From this I gather that the country is becoming more and more liable to them and that they have steadily increased in number during the last few centuries.

国中に地震の襲来し、そして日本のある島や地域だけがその被害から免れることはありえない。ある日本人役人のお世話で、これまで日本で起きた地震の記録を手に入れた。それを見てみると、過去数世紀において間違いなく大地震が増えていることがわかる。

   Thus there was but one destructive earthquake in the 5th century, which happened in the year 415 ; none other is known to have occurred till the 10th century ; one more occurred in the 11th century, another in the 13th, 2 in the 16th, 10 in the 17th, 13 in the 18th and 15 in what has already passed of the 19th century. The average of this century therefore has been one destructive earthquake in every 5 years, while 300 years ago there was but one in 50 years.

5世紀、正確には415年に破壊的な大地震が発生したが、その後、10世紀までは発生が知られていない。次いで、11世紀と13世紀にそれぞれ1度、16世紀に2度、17世紀に10度、18世紀に13度、19世紀に15度、それぞれ起きた。今世紀においては、平均すると5年ごとに大地震が起きており、50年に一度の300年以前とは明らかに違う。

   The following is a list of the most destructive which have occurred throughout the country.

   In the 15th year of the reign of the 20th Emperor -- in the year 415. A  destructive earthquake happened.

   Another in the year 937, another in the year 1021, and another in the year 1292, which was fan, worst at Kamakura.

   One felt worst at Tsuruga and Totomi in the year 1588.

   One which destroyed many houses and took many lives at Kioto and Fushimi in the year 1595.

   One at Yedo which destroyed the Castle and many Daimios' residences in the year 1647.

   Another at Yedo which knocked down, many houses and killed a great number of people in the year 1649.

   One in the province of Iyo which brought down the retaining walls of the Castle of Matsi-yama and destroyed many houses in Uwadjma in the year 1649.

   One severely felt throughout the 8 provinces surrounding Yezo in the Year 1650.

   One which partially destroyed the Castle of the Mikado nt Kioto and ruined the castle of Nijo in the year 1661.

   One felt in the province of Echigo in the year 1661.

   One felt in the Iand of Yezo in the year 1662.

   One which again partially destroyed the castle of Nijo near Kioto when the shocks lasted for 8 hours in the year 1662.

   One felt at Niko in the year 1682.

   One felt at Diwa in the year 1693.

   One felt throughout the 8 provinces surrounding Yedo. Walls of outside and inside moats of Castle of Yedo destroyed. Felt very severely at Odawara where many houses were destroyed and numbers of people killed. Tidal waves also broke along the coast at the same time anti caused enormous destruction. The road leading through the liakou6 pass closed up by the alteration in the surface of the earth in the year 1702.

   One severely felt in Yodo in the year 1715.

   Ono felt throughout the 13 provinces surrounding Kioto—when many parts of the earth opened up -- and enormous tidal waves occurred in the year 1716.

   One felt severely in the neighbourhood of Fusiyama. At this time, which was on the 22nd of the 11th month, fire burst from a place called Moto hashiri kuchi at the base of Fusiyama -- there was a fearful noise like thunder, and a black gritty sand was thrown into the air which caused darkness to come over the whole surrounding country. Even in Yedo lanterns were used in day One. During the night of the 22nd this continued, but on the morning of the 23rd the sky WU seen. On the 25th darkness again came on, black sand fell like rain and it During cleared up again on the 28th. A small mountain rose up on the side of Fusiyama, at this time which has been called Ho-yae-san from the period in which the occurrence took place which was in the year 1716.

   One felt at Nagasaki when there wore more than 80 shocks in one day and night in the year 1725.

   One kit in the province of Echingo which occurred during a heavy storm of wind and rain. The Earth is said to have opened up and belched forth water so that the plains were like rivers, anti men, horses, cattle aid all animals hi the neighbourhood were drowned in the year 1726.

   One felt at Kioto in the year 1750.

   One felt in the province of Echingo when the earth trembled 30 times in 20 hours, a will was cracked, the earth opened and 16,300 lives were lost in the year 1750.

   One felt at Awomori when the falling houses took fire and caused the death of a great many people in the year 1765.

   One felt in Yedo in the year 1770.

   One felt in Yedo dittoing the same year 1770.

   One felt in Yedo in the year 1782.

   Frequent severe earthquakes in Endo in the year 1789.

   One felt at Diwa when both the hills and the plains were cracked and the earth opened up in the year 1803.

   One felt in the Island of Sado when there were constant shocks for 19 days from the 1st of the 1st month to the 18th of the 6th mouth in the year 1809.

   One felt in the vicinity of Yedo, but worst at Kanagawa and Hodongaya, where many houses were destroyed in the year 1811.

   One felt in the district of Moto in the year 1818.

   One felt in Oshiu in Yezo when the earth shook more than 150 times in the year 1821.

   Frequent severe earthquakes at Yedo in spring time in the year 1824.

   Frequent severe earthquakes at Yedo in autumn of same year 1824.

   One felt in the province of Echigo in the year 1827.

   One felt in Kioto when the Mikado's residence, many of the temples and the Castle of Nijo were destroyed. The earthquakes commenced on the 2nd of the 7th month, they partially discontinued on the 20th of the 8th month, but were not entirely quiet until the following year, in the year 1829.

   One felt in the vicinity of Fusiyama in the year 1833.

   One felt in Sendai whoa the castle was destroyed and great destruction was caused by tidal waves in the year 1833.

   One felt in the province of Shinano which destroyed many temples and houses numbering in all about 5,000 - 700 people were killed and 1,460 wounded. The earth opened and swallowed 16 houses - sin the year 1846.

   One felt at Kioto and Osaka - in the year 1851.

   Frequent earthquakes throughout the 8 provinces sure rounding Yedo, which were also felt at Kioto and in the Islands of Sikok and Kiusiu. The earth was not quiet for one yeaｒ- in the year 1854.

東京周辺の8地域ではしばしば地震が起き、また京都や四国・九州でも頻発する。1854年では地面は一年を通して安定していなかった。

   The most recent which has happened was most severely felt at Yedo, where the trembling of the earth continued for one month and gave 80 severe shocks. Many houses were knocked down, their timbers took fire and conflagrations commenced at 45 different places. About 120,000 lives were supposed to have been lost. This occurred in the year 1855.

つい最近発赤したものは江戸で激しく感じられた。地面の振動は一月ほど続き、その間に80回もの地震があった。多くの家屋が倒壊し、木材が焼失し、45箇所で大火事が発生した。

   Those parts of Japan most subject to earthquakes are, strange to say, the vicinities of the two capitals. Thus out of the 43 severe earthquakes which have taken place during the last 600 years, 9 have occurred at Kioto and 13 at Yedo. The province of Echingo is next in numbers and has had four earthquakes. Yezo has been visited twice, as also Diwa and the neighbourhood of Fusiyama -- while Nagasaki, Sado, Sendai, & c. have only suffered from one disturbance.

地震の襲来に襲われるのは、不思議なことに二大都市の周辺である。過去600年の間に起きた43の大地震の内、京都で9回、江戸で13回起きている。それに次ぐのは越後の4回、蝦夷の2回、長崎、佐渡、仙台などは１回であった。

   But, while the country, as is abundantly shewn above, is liable to very severe and an increasing number of earthquakes, the system of construction in the buildings has not been well devised to withstand such visitations. The more solidity and weight in a building and the greater its inertia, the less liable it is to derangement from a sudden movement of its foundations; but, at the same time, it is essential that the strength and connection of the materials in the walls should be proportionate to their weight and mass. As a general principle preference should be given, both on account of durability and stability, to the adhesion of bricks or stone and mortar in a solid well built wall, over ordinary wooden buildings.

大地震が多発するにもかかわらず、この国ではそれに対抗する建築システムを工夫してこなかった。建物のより大きな堅実性と重量、そしてより大きな慣性、それが小さければ基礎の突然の運動に攪乱されてしまう。同時に、壁の材料の強度と接合が重量と嵩に対して適正でなければならない。

   It might be that a wooden erection could be constructed with its frame work so tied and braced together as to render it almost perfectly secure against any earthquake, short of an upheaval or breach in the surface of the earth ; but this would be an expensive, thriftless and impracticable style of construction. Whereas on the other hand, a stone erection need not be more than ordinarily massive to make it capable of resisting any shock not of extraordinary violence. But in stone houses it is absolutely necessary that the masonry should be executed in a proper manner, the great point to whirls attention must be given being that a perfect bond is maintained throughout the entire building.

   Mr. Mallet in his history of the Neapolitan earthquake of 1857 gives many proofs of the truth of this. He says---" When the masonry consisted of round lumpy quadrated avoids of soft limestone, the whole dislocation occurred through the enormously thick ill-filled mortar joints and almost all buildings thus formed fell together in the first movement in indistinguishable ruin"—" Where the masonry was of the best class, and such as would he an recognized in England, the buildings thus constructed stood uninjured in the midst of chaotic ruin.

   Some examples of this will be found in the second part, none more striking than the Campanile of Atena, a square tower of 90 feet in height and 22 feet square at the base, in which there was not even a fissure while all around nearly was prostrate." "Indeed it was evident that had the towns generally been substantially and welt built or rather the materials scientifically put together, very few buildings would have actually been shaken down even in those localities where the shocks were most violent.

   Thus the frightful loss of life and limb were au3 much to be attributed to the ignorance and imperfection displayed in the domestic architecture of the people, as to the unhappy manna condition of their country regards earthquakes."

   A very striking example of the advantage of solid construction over lightness said want of strength WEIS seen Hot many years ago at Manila, when an earthquake levelled almost the entire town and left the Stone Lighthouse at the harbour, which is a column of masonry of great height, standing by itself perfectly unharmed. From the vast and handsome edifices which may be seen in most countries icy Europe liable to earthquakes, we may conclude that their inhabitants have acknowledged the correctness of this principle, anti it cannot therefore be urged on sound grounds that it is owing to the liability of Japan to earthquakes that its people have never desired or made an effort to build other than wooden houses or to make these of any but of the most flimsy description.

   The general poverty of the people and their extremely simple habits may account for the simplicity of their dwellings, and as their habits become more refined and luxurious it is very probable that the internal comforts of their houses will also improve.

   Six hundred Years ago the dwellings of the English were constructed in the roughest manner of wood and clay. The inmates ate and slept in one room and privacy was perfectly unknown. In the beginning of the 15th century the houses began to be divided into rooms and private apartments. Shortly afterwards glass windows and chimneys were introduced, and stone buildings were erected the ruins of some of which are in existence at the present day. Gradually improvements were one by one effected, until the modern English residence was produced.

VI>"Earthquake and Buildings" in Japan Gazzette, March 1877.

   All countries subject to seismic influences, endeavors to solve the there  all-important question of how buildings can be constructed so as best to resist the effects  of earthquake shocks, must have a peculiar interest. That man who shall give to  the world some system of building which will materially reduce, if not altogether annihilate, the risk daily and hourly run by the inhabitants of countries liable to the earth convusions which involve such terrible destruction, not of property only but of human life, as was wrought here in 1856, will deserve a prominent place in the roll of the benefactors of his species.

   The work which we publish below is by a gentleman of practical experience. His remarks and suggestions, as they will appear in these columns, have by this time been read before, and discussed by, a learned society of engineers in Europe, whose debate and decision upon the matter we shall receive in due course. We do  not claim infallibility for the author; but we cannot deny him the credit of patient research, added to considerable ingenuity and a broad scope of view. His work contains much which will, we think, be new to all our

readers; as for instance where he boldly combats the theories that the mode of build  ing prevailing among the Japanese is well calculated to resist horizontal shocks of

 earthquake, and that the system of heavy roofing is part of that design instead of, as he holds, a mere consequence of it.

   But on this and the remainder of his interesting subject we will let our author speak for himself in his paper, which will be found very much, and as attractive as any dissertation,

which from its nature is compelled to deal largely in technicalities, can be expected to be. For the furtherance of the object he has in view, namely the introduction into

 Japan of a simple system of domestic architecture, which shall allow the people to live free from the apprehension of the hourly danger they are now in of the walls and roofs

of their dwellings crumbling about their ears, he invites discussion, and asks that any fallacies which may be discovered in his theory shall be exposed. For the purposes of such

debate, calculated to be of great practical utility, our columns are always open.

An Essay on JAPANESE BUILDINGS AND ON BUILDINGS IN GENERAL, considered IN CoNNECTION witH EARTHQUAKEs :

AND A DESCRIPTION of A systEM DESIGNED TO GIVE WERY CONSIDERABLE SECURITY TO CONSTRUCTIONS IN MASON RY,

PART I.

 JAPANESE BUILDINGS AND BUILDINGs in GENERAL CONSIDERED IN CONNECTION WITH EARTHQUAKES.

    The pretended solidity of Japanese buildings against the effects of earthquakes has been much vaunted ; and if we are to believe  some persons they are models of their kind

in this respect; but we have come to the conclusion that, if earthquakes have not caused greater destruction than has so far occurred to Japanese buildings, the cause

is to be found rather in the restricted dimensions of the constructions themselves, than  in any merit in the principles on which they are built.

   All Japanese houses are of wood: they  have often oul, a ground floor rather low :  the first floor, if they possess any, is only about seven or eight feet high ; and it is a rare occurrence to find houses having a second floor. The method of construction may be easily imagined from the following description. Hardly any or no foundations.

   A basement, or simply blocks of stone on which rest ground-plates receiving the feet of the posts, or even blocks of stone where on rest posts which themselves receive the

ground-plates Posts, few in number, and between which are placed those panels with squares of paper, which have given rise to the saying that Japanese houses had paper walls. And in fact all the internal divisions of the houses as well as the frontage walls are so made,  that, when all these sliding panels are taken away, nothing remains but the flooring,

some posts here and there, and the ceilings.

   An utter absence of ties or bearers, whether at top or bottom of the said posts.  A very heavy roof-frame of timber, composed of several principal beams or large horizontal pieces, placed one above the other, on which rest posts placed vertically without braces, and of height arranged according to the degree of inclination of the roof: bind ing-rafters joined to the extremities of the horizontal tie-beams placed one above the other, and of these posts: some hip-corners only : some rafters: some thin planks of white wood : shingles: some plaster in earth or lime; and then heavy tiles.

   This is a tolerably succinct description of how a Japanese house is built. It will be seen that such a method of construction may  apparently present certain advantages of

security against earthquake shocks of little violence, by reason of the amount of oscillation which its comparative want of rigidity will allow it to bear; but we shall see further

 on that it is very badly designed to resist any violent horizontal shocks.”

   In the first place the Japanese rest their structures on the ground only, without deep foundations, in order, say they, to offer no resistance to the lateral displacement of the

 building during the horizontal oscillations of earthquakes. This absence of foundations  appears, at first sight, logical enough ; but if we follow the subject further it will appear more difficult to admit the possibility of establishing surfaces sufficiently slippery for the effect to be thoroughly produced.

    We think rather that, in consequence of the weight of the construction, and the nature of the points of contact with the soil, it must be admitted that the house will follow, at

 least in great measure, the movements of the soil. At all events, and following up  the Japanese principle, the buildings with ground-plates resting on blocks of stone

would be preferable to those in which the ground-plates rest throughout their entire length upon basements of masonry; and the advantages of the first over the second system would be in proportion to the extent of surface in contact with the soil.

    We may presume that the experiment of the sheet of paper which can be drawn from under a heavy object without displacing it, provided the action is very rapid, plays a

large part in the Japanese principle of the sliding of a building upon its foundations. But they forget that the heavy object would be drawn along with the paper, if the action

 were not performed with suilicient rapidity – that is to say if the quickness of motion imparted to the paper were not sufficiently great. Besides, it is scarcely admissible that,

in an earthquake, the horizontal waves or shocks can ever attain a speed corresponding with that of the sheet of paper in the experiment which we have just quoted; and,

even if some should reach it, we must not  forget that others may be very disastrous and yet fall short of it, and that most frequently, if not always, the house will be drawn along with its foundations, as is the case in the experiment of the weight and the sheet of paper, when the speed given to latter is not sufficiently great.

    Among other projects, it has been proposed, in San Francisco, to rest the wooden structures of California upon convex surfaces and even upon balls. We have been told that, in Japan, a light-house had been built upon balls; but that experience had condemned the system ; and that it had been necessary to reconstruct the light-house upon

the ordinary principles.f

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* The opinion of a very intelligent Japanese gentleman, with whom we had some conversation on the subject of earthquakes the other day, coincites with that of the author in this particular. He cited, as an irrefutable proof of the instability of Japanese structures under severe shocks of this nature, the terrible earthquake of 1856. That earthquake was horizontal; and in Yedo and the neighboring districts comparatively few houses were left standing, while the native records of the  calanity give a total of 120,000 persons destroyed Before that time, our informant states, all tha tnercantile houses in the capital were two stories high, and their roofs were ornamented, while their weight was increased, with the addition of heavy ornamental pieces, at the four corners and on the extremities of the apex, known as on-lawara. He adds that one-storied buildings, previous to that

time, were rarely seen in Yedo. Warned by the experience of the terrible disaster which had come upon their city, the survivors, in rebuilding the town, carefully avoided either constructing two-storied houses, or weighting the roofs with ornamental tiles. 

   They neglected the main point, however, namely, to secure a style of building which should offer the maximum of resistance to seismic influences to a minimum cost of construction. Further, as in the lapse of time the lessons of experience so dearly bought twenty years ago have lost much of their force, the old fashion of building has again cone

into favor; and hence we see inany Japanese houses newly built, especially in Tokio, two-stories high, an with the heavily weighted roofs which the author an our Japanese friend holl to be such terrible sources of lang ºr in cases of severe horiºonial earthquakes.--- i. J.G.

+ This is the light-house alluded to in a paper on

“Japan Lights,” read by Mr. R. H. Brunton, on

the 14th November last, before the Institution

of civil Engineers in Lon lon. We quote below.

the portion of the paper referring to the matter;

and mention incidentally that Mr. Brunton would

appear to be in favor, if anything, of the principles

applied, in the existing system of Japanese ar

clutecture, to buildings of small size, with a view.

to the counteraction of seismic shocks.- Ed. J. G.]

“The liability of the country to earthquakes

was an important point for consideration in the

construction of the lighthouses. Messrs. D. and

'1'. Stepuenson, who designed the apparºus, devis

ed what had been named an aseismatic joint, by

means of which a break was made in the continuity

of a structure, and the propagation of a shock from

the foundation upwards was prevented. This was

accomplished by the introduction of balls working.

in cups placed between the platforms, the lower

platform being fixed to the foun lation, and on the

upper platform the superstructure was erected,

This arrangement was sanctioned by the Board of

Trade for the apparatus of the first lights ordered ;

but, in the author's opinion, it was defective, in so far

that the free motion of the upper, over the lower,

part, of a structure would, on the occasion of dis

turbances, such as a gale of wind, give rise to a

distressing, and in some cases probably a destruc

tive, motion in the superstructure. There being

two movements in all earthquakes, one ten ling

to overthrow, and the other to restore equilibrium,

if a building could be constructed with a sullicient,

power of resilience, its destruction could not occur,

unless the oscillation went beyond its limit of

 equilibrium. The houses in Japau has be a evident

--------

 These various projects for sliding or roll

ing, are only improvements upon the Japa

nese principle which we have indicated; and

it will be understood that they are only ap

plicable to light structures in wood, and

under quite peculiar circumstances. .

We come to the conclusion, then, that,

 if the idea of supposing a building sliding

upon its foundation has a logical appearance,

it is in reality only fantastical, and from a

practical point of view should be considered

altogether inconsequent. In fine, we believe

that it is necessary to endeavor to give, by

more rational means, to structures the se

 curity which is so much needed to resist the

effects produced by earthquakes of consider

able violence.

The absence of tics and of bearers to con

 solidate the joints of posts with the ground

plates and with the upper framework is, in

the opinion of the Japanese builders, a con

sequence of the preceding principle. “If,”

say they, “we admit that our constructions

 should glide upon the ground during hori

zontal oscillations, it is, nevertheless, to be

 feared that they will only do so imperfectly,

and thon the play left to the posts in their

joints remedies the imperfection of the first

system.” But, as, with the Japanese, every

thing is the result of the experience of many

centuries, this necessity of suppressing all

ties, bearers, and braces proves superabund

antly the inefficacy of the principle of a build

 ing sliding upon its foundations, although it

indicates, at the same time, that a certain

 elasticity is favorable to resistance, by build

ings, to horizontal shocks. For would it

not be more logical, if the gliding were pro-