OF THE SHAPE AND EXTENT OF THE SEISMIC AREA. 85 



CHAPTER VIII. 



OF THE SHAPE AND EXTENT OP THE SEISMIC AREA. 



On account of the vast extent of country over which this earthquake 

 was felt, of the unsatisfactory nature of the reports obtained from most of 

 the places at which it was felt, and of the unsettled and uncivilised state 

 of other districts where the shock must have been sensibly felt but no 

 records could be obtained, we are not able to lay down isoseismal lines as 

 numerous, or with the same accuracy, as is desirable. We can, however, 

 form a very good idea of the shape and extent of the area affected by 

 the shock ; and with this object in view I have laid down on the map 

 No. 1 a line which marks, as near as can be ascertained, the boundary 

 of the area over which the shock was perceptible to the unaided senses. 



Starting from a point on the western shore of the Bay of Bengal, 

 not far from Hidgellee, the line runs north-westward to Hazaribagh, 

 thence northward to Patna ; it then passes over a tract in which its 

 course is uncertain, and the next definite point is Darjiling, which 

 must have been situated not far from the boundary of the area whose 

 limits we are describing ; far to the east of this station we hear of the 

 shock being severely felt at Lakhimpur ; we may therefore take the line 

 as passing through the Himalayas, and perhaps extending beyond them on 

 the north ; eastward again we hear of the shock being severely felt at 

 Dibrughur, and from further east we have no reports and could expect 

 none. At Manipur the shock was very severe, and this, combined with 

 the report that the shock was felt in Upper Burmah, justifies us in 

 taking the line down through Upper Burmah to Kussilong and Chit- 

 tagong. The boundary thus drawn includes an area of roughly oval 

 form, from 650 miles long from north-east to south-west, and 400 

 "miles in the co-ordinate direction of north-west and south-east, thus 

 enclosing a total area of a quarter of a million (250,000) square miles. 



We have not sufficient information to enable us to draw any isoseis- 

 mal lines within this area, but on the map I have laid down part of a 

 line which would enclose that area over which the shock was really 



( 85 ) 



