1888.] occurred at Dacca on April ItJi, 1888. 217 



action would be the posterior, and we have evidence that this was so in 

 the violence of the destruction to the east of the first track from north 

 to south. The anterior radius being tilted most upwards would at first 

 have the feeblest power, and it is the case that the least destruction 

 done was in the river bank straight in front of the violent gale that 

 broke through the trees from the north. If the vortex had gradu- 

 ally formed, one would have expected a more equal distribution of power 

 around it, instead of its being chiefly at first on two sides. 



The theory that the tornado already formed was travelling rapidly 

 from north to south before it struck ground, also explains the reason for 

 its starting at once in a south-easterly direction. The resistance of the 

 ground was at first offered solely to one radius, the right or advancing 

 lateral one. The result was equivalent to that of a sudden powerful 

 push to the left, that is, to the east of the direction in which it was pre- 

 viously travelling. The experiment of offering resistance to a humming 

 top at a corresponding point would illustrate the effect of the resistance 

 of the ground to a tornado descending upon it in the way in which I 

 suppose this one did. 



The possibility of a tornado travelling in the air may a.ppear doubt- 

 ful to some, but the probability of its being able to do so, and at great 

 speed, receives confirmation from what I consider to be the progress of 

 this very tornado after it left Dacca. I have said that when the vortex 

 reached the Sankari Bazar it seems to have risen rapidly into the air, for 

 the reason that only the upper stories of the high houses of this part of 

 the town were seriously damaged. It seems after leaving Dacca to have 

 travelled in the air due south for a distance of 20 miles, and to have 

 struck down again in the south of the Munshiganj subdivision of this 

 district, destroying 5 or 6 villages, and causing 60 to 80 deaths. The 

 time it took to travel that distance was not more than 20 minutes to 

 half an hour. It came upon the people in the west suburbs of Dacca 

 just as they were about to sit down to their evening meal, a few minutes 

 after 7 p. m. It reached the neighbourhood of Rajabari in the south of 

 Munshiganj just as they had finished their evening meal, and were pre- 

 paring for their post-prandial smoke, that is, about 7.30 p. m. 



It may be objected that it was not the same tornado which took 

 these villages in Munshiganj, but another and independent one. But 

 the improbability of two different and independent tornadoes, forming 

 and travelling together on one evening in this part of India, where a 

 tornado has never been known before, is, to say the least, very great. 



Since writing the above, I have visited the villages referred to in the 

 south of the Munshiganj subdivision. The people say it came from the 

 north-west. It first struck a village called Dohori, then Barakoer, 

 Banuri, Hashail, Silbaran, Majgaon, and Bagbari j a course altogether 



