1890.] Lieutenant- General Mainwariug — Oa the ' Barisdl Guns.' 209 



4. Theory on the origin of thesouwls Jcnoiun as the ' Barisdl Guns.' — 

 By Lieutenant- General MAiNWARiNa, B. S. C. 



(Abstract). 



After enumerating the various theories hitherto given and stating his 

 inability to accept any of them as conclusive. General Mainwaring formu- 

 lated his theory as follows : " The vast river formed by the coalescence of 

 the Ganges, Brahmaputra and Megna with the numerous large streams 

 chiefiy meeting in the mouth of the misnomeued Megna, here resolves 

 itself into a broad sea ere coromiugliug with and augmenting in no small 

 degree the waters of the Ocean Bay. This mighty river and all the 

 enormous and innumerable volumes of water-mouths of the Ganges 

 which jjour southward into the Bay carry with them innumerable quan- 

 tities of mud and fresh decaying and decayed vegetable and other 

 oi-ganic matter. All this composes the bed of the Bay. In it are gei'- 

 minated vast and ever accnmulatiug stores of gas. This, without 

 doubt, partly escapes, gradually, by ebullition but a far greater portion 

 is confined in the superincumbent mud. This when collecting in quan- 

 tity too great and forcible to be restrained, bursts forth and discharges 

 itself into the air thus occasioning the loud report." 



Though anxious to obtain evidence of the escape of gas in quantity 

 sufficient to cause these sounds, Gen. Mainwaring failed because during 

 the monsoon season the boatman refused to proceed to sea. The latter 

 half of the paper was taken up with accounting for various peculiarities 

 observed in the sounds— such as (1; the double sound so frequently 

 heard (2) their occurrence during the monsoon season, (3) their beincr 

 heard far inland. The first is explained by the gas not all escaping at 

 once, being followed at a short interval by the remainder ; the second 

 by the disturbed water in the rains stirring up the mud and relievino- 

 the gas ; the third by the existence of lakes or marshes near the jilace 

 wdiere the sounds are heard, and in which similar decomposition of vege- 

 table matter occurs. 



Babu Gaurdas Bysack remarked that according to General Main- 

 waring the sounds of the ' Barisal Guns' are pi-oduced by the action of 

 .river Avater on the mud, bed or bank, aiid that of gas generated from 

 vegetable matter, but these conditions were certainly nob confined to 

 the rivers in Backerguuj, or in the eastern districts, where the myste- 

 rious phenomenon occurs. They are equally, or perhaps with greater 

 force, ajjplicable to the Hughly river which brought down much veo-e- 

 table matter and yet no sound of the kind is ever heard at Diamond 

 Hai'bour or in the vicinity of Calcutta. He has heard the sound at 

 Tnmlook, but the fact that the river Rupnarain on which that town 



