148 



KNOWLEDGE. 



[July 2, 1900. 



is shown in Fig. 1. It will be seen that its boundary 

 (indicated by a dotted line) can only be traced for part 

 of its course; for one-third of the area, Mr. Oldham 

 estimates, lay in regions from which information 

 was unobtainable, while another third is sparsely in- 

 habited by ignorant and illiterate tribes. But, not- 

 withstanding this, the shock is known to have been felt 

 over an area of at least 1,200,000 square miles. If we 

 include the detached region to the west, near Ahmeda^ 

 bad, the portion of the Bay of Bengal in which the 

 shock would have been perceptible if the sea had been 

 replaced by land, and a large part of Thibet or Western 

 China, from which no rejjorts have come but in which 

 the shock was certainly sensible, this estimate, great as 



Of the other two curves on the map in Fig. 1, the con- 

 tinuous line represents the epicentral area, and the broken 

 line bounds the district in which serious damage was 

 done to masonry. The area of the latter is not less than 

 145,000 square miles, or 160,000 square miles, if we 

 include the part from which records were not obtain- 

 able.* Calcutta lies within the area of destruction, 

 and a good deal of damage was done to buildings in 

 the city ; but this, as Mr. Oldham points out, was 

 largely due to their peculiar mode of construction. 



Figures, such as those quoted above, give but little 

 idea of the vastness of the areas concerned. Transfer- 

 ring them to countries with which we are better 

 acquainted, we may say that the disturbed area was 



5),a!o 



^jMiTncdafcad, , 



Calcut tcL 



Fig. 1. — Map of the Disturbed Area of tlie Indian Eartli<iuake of 1897. 



it is, must be raised to about 1,750,000 square miles. 



It does not appear that any other earthquake, of 

 which we possess reliable rccoi'ds, has been felt over so 

 wide a region. Until 1897, the great Lisbon earthquake 

 of 1755 had no competitor in this respect; but of its 

 disturbed area we have no exact knowledge, for the 

 focus was situated beneath the Atlantic Ocean. There 

 are some doubtful records of the shock having been 

 actually felt at Reading and in Derbyshire, and also 

 at Milan and Turin. If we exclude these, Mr. Oldham 

 estimates the total area over which the Lisbon earth- 

 quake would have been felt, had it all been dry land, 

 as not more than a million square miles. 



only a little less than half the size of Europe; the 

 region in which serious damage occuiTed to masonry 

 was more than twice as large as the whole of Great 

 Britain ; while, if the centre of the epicentral tract had 

 been in Birmingham, nearly every brick and stone 

 building in England and Wales from York to Exeter 

 would have been levelled to the ground. 



* Mr. Oldham does not refer to the corresponding area for the 

 Lisbon earthquake. I am not prepared to make even a rough estimate 

 of its extent; but, if the reports of damage in .Spanish towns (witliout 

 speaking of those in Morocco) are correct, it must, I think, have been 

 ill excess of the higher of the above figures. 



