NATURE 



265 



FHURSDAY, JANUARY 21, 1SS6 



THE EAST ANGLIAN EARTHQUAKE OF 18S4 

 Report on the East Anglian Earthquake of April 22, 

 1884. By Raphael Meldola, F.C.S., &c., and William 

 White, F.E.S. Drawn up by R. Meldola, and read in 

 abstract at the meeting of the Essex Field Club, 

 February 28, 18S5. '(London: Macmillan and Co.; 

 and the Essex Field Club, Buckhurst Hill. 1885.) 



FORTUNATELY for this country we have not been 

 called upon to notice a report of such an earthquake 

 as that which is chronicled in the volume before us since 

 this journal came into existence. Indeed, the authors 

 state that no shock approaching it in intensity has been 

 experienced in the British Islands for at least four cen- 

 turies. A brief notice of the occurrence was given in our 

 columns (vol. xxx. pp. 17 and 60) by Mr. Topley, and we 

 now have a complete scientific account drawn up by Prof. 

 R. Meldola and presented to the Essex Field Club as a 

 special memoir embodying the results of his investigation 

 in conjunction with his colleague, Mr. William White. 

 The book consists of about 225 pages of readable matter 

 with four maps and numerous illusti-ations, and the Essex 

 Field Club has certainly earned the gratitude of scientific 

 men in enabling the authors to give publicity to this final 

 result of their labour. 



Earthquakes may be considered from three distinct 

 points of view : dynamical, geological, and meteorological 

 or cosmical. The first deals with the purely mechanical 

 aspect of earthquake motion, the second with the imme- 

 diate cause or causes of these disturbances and their 

 effects as determined by geological conditions, while the 

 last, which is at present the most obscure branch of the 

 subject, deals with the periodicity of earthquakes and 

 their connection with other natural phenomena. The 

 present shock is dealt with from each of these stand- 

 points. 



Of the eight sections into which the Report is divided 

 the first is entirely historical, and the authors give a cata- 

 logue of all the British earthquakes which have produced 

 structural damage, the records commencing in a.d. 103 

 and ending with the Nottingham shock of 18S1, which 

 slightly damaged a building at Tackley. This list com- 

 prises about sixty records, and the authors acknowledge 

 their indebtedness to Mallet's British Association Cata- 

 logue, which has greatly facilitated their work of com- 

 pilation. One very interesting circumstance brought out 

 by this part of the inquiry is that the seat of the present 

 earthquake has been exceptionally free from seismic dis- 

 turbance since the beginning of authentic history, and it 

 further appears that there have been altogether only about 

 half-a-dozen shocks in Britain since this period which 

 can be compared in their destructive effects with that of 

 1884. 



The second section gives a brief description of the 

 preparation of the Report and the methods adopted for 

 securing the most complete and trustworthy information 

 as soon as possible after the event. Amongst those to 

 whom the authors express their obligation are Mr. G. J. 

 Symons, F.R.S., who had himself made a personal in- 

 spection of the scene of damage the day after the shock, 

 Vol. xxxiii.— No. 847 



and Mr. J. C. Shenstone, of Colchester, who appears to 

 have supplied much valuable local information. 



Under the third section, which is headed " General 

 Characters of the Disturbance," we have a statement as 

 to the extent of the shock, which brings out very forcibly 

 the unpleasant fact that our little island is not quite so 

 " tight," as the popular song would have us believe. It 

 seems that the sensible vibrations extended over at least 

 50,000 square miles of country. An estimate of the 

 intensity is also given which is compared with that 

 of the great Lisbon catastrophe of 1755, the authors 

 arriving at the conclusion that the present shock was 

 about one-twentieth the intensity of the former. In 

 support of the statement that " the earthquake occurred 

 during a period of general seismic activity throughout the 

 world " we have a list of all the British and the more 

 violent of the European earthquakes which have occurred 

 since the beginning of the year 1881. We need only 

 remind our readers that during this period occurred the 

 disasters in Ischia and Chios, the cataclysm in the Sunda 

 Straits, and, more recently, the great Spanish earth- 

 quakes, all of which have already been noticed in our 

 columns. With reference to the meteorology we are 

 informed very explicitly that " the evidence is conclusive 

 that no special meteorological conditions preceded, ac- 

 companied, or succeeded the disturbance of last April in 

 direct relationship to that event." 



In treating of the nature and duration of the movement, 

 and other points of importance which find place in this 

 third section, the authors give a concise account of the 

 general characters of earthquake motion as derived from 

 the observations of modern seismologists, and especially 

 from those made in Japan by Profs. Milne and Ewing, to 

 whose labours constant reference is made throughout the 

 Report. The following conclusion, supported by observa- 

 tions made at Heybridge and Ipswich, is arrived at : — 



" There is every reason to believe that the earthquake 

 with which we are dealing was precisely similar in cha- 

 racter to those frequent shakings which have been so 

 thoroughly studied in the Plain of Yedo. As in the case 

 of the latter, if our earthquake had been made to trace 

 the story of its own movement on a series of seismo- 

 graphic plates, we should no doubt have seen the gradu- 

 ally commencing tremor increasing in amplitude and 

 complexity till the ' shock ' and destruction occurred, and 

 then again dying gradually out." 



In the fourth section we have a discussion of the nature 

 and amount of the structural damage, from which it 

 appears that in an area of fifty to si,xty square miles 

 damage was caused to 12 13 houses and cottages, twenty 

 churches, and eleven chapels. 



The " Descriptive Report," which comprises the next 

 section, occupies over 100 pages of the volume, nearly 

 one-half of this portion being devoted to a detailed de- 

 scription of the observations in the area of structural 

 damage made on the ground by Prof. Meldola, Mr. T. V. 

 Holmes, F.G.S., President, and Mr. W. Cole, Secretary, of 

 the Essex Field Club. Many illustrations of peculiar forms 

 of damage are given, and there can be no doubt that the 

 observations recorded in this section will be not only of 

 local interest but also of use to engineers and others who 

 occupy themselves with the important question of con- 

 struction in earthquake countries. 



