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EXCERPT from Preliminary notice of the Bengal Earthquake of 14 th July 1885, by H.B. Medlicot (1885) Records of the Geological Survey of India Vol. XVIII, Part 3 p. 156-158 Observations are being made by officers of the Geological Surve y where the shock was most severely felt. Mr. C.S. Middlemiss is taking notes at Serajganj, Sherpur (in the Bogra district), Maimansing, and Dhaka (Dacca); and Mr. P.N. Bose is visiting Nattore, whence some peculiar effects have been reported. The time of the occurrence was rigorously fixed for Calcutta by the stopping of the three regulator clocks at the Meteorological Observatory, from which the time signals to the port are made, as checked by daily astronomical observations; the hour was 6h24m12s, on the forenoon of the 14 th . The clock stands due north-south, facing east. As to the direction at Calcutta, the most reliable observation I have heard of was that by Mr. E.C. Cotes, of the recently filled cistern of a gas- holder on the premises of the Indian Museum; the water was seen to spill to a little east of north. This is, too, the direction suggested by the general report of damage done, which is very markedly concentrated in the upper deltaic area traversed by the Brahmaputr a. In parts of this area slight shocks and tremors have continued since the main shock until now. No notice of the shock has been reported from Cachar or upper Assam. Cracks in the walls of houses are numerous enough, but it is very difficult to make sure that they are not old ones that had been plastered over. The most distinct case of overthrow that has come to notice was that of a heavy plaster cast leaning against the north wall in a recess some 12 feet above the floor in the palaeontological gallery of the museum, but it must have been in a dangerous state of unstable equilibrium. The area indicated is, so far as I know, a hitherto unsuspected position for a seismic focus, at least from recorded earthquake observations; but it is noteworthy that within that area, north of Dhaka and west of Maimansing, lies the ground known as the Madhopur jungle, which was described by Mr. James Fergusson in his admirable paper on the delta of the Ganges (Quar.Jour.Geol.Soc.London, XIX, p.329, 1863) as due to an upheaval, “which there is every reason to suppose took place in very recent times.” It is described as presenti ng a more or less scarped face of deltaic deposits along its western side, raised about 100 feet above the actual alluvial area, and sloping eastwards under the old bed of the Brahmaputra, and losing itself in the Sylhet jheels (swamps). This form is certainly very suggestive of an actual upheaval along the western edge, and this line, running past the end of the Garo hills on towards Sikkim (where the recent earthquake was very sensibly felt), would approximately suit for the axis of the seismic area as now indicated. There is another feature described by Mr. Fergusson that must be taken into consideration in the present discussion, namely, the change that occurred early in this century in the course of the Brahmaputra. When Major Rennell surveyed these
