440 THE ERUPTION IN THE STRAITS SETTLEMENTS, 



The question now arises whence this dust came. Two sources 

 only appear possible, and which have been mentioned above. 



The dust was distributed from a centre in the neighbourhood of 

 Karakatoa with exti-aordinary velocity, averaging, according to 

 the data of the first appearance of the after glow, 2,000 miles per 

 day. This great rapidity only lasted two days, later on the 

 distribution was very slow in comparison, averaging only 100 miles 

 per day. This great rapidity of the distribution at first seems to me 

 to prove, that the dust must be of meteoric origin. If a cloud of 

 meteoric dust struck the atmosphere of the earth, which rotating 

 very rapidly in the tropics moves in a different direction from the 

 dust cloud, falling towards the earth, it would of course disperse 

 this dust cloud immediately, and in this manner the great rapidity 

 of distribution at the beginning is explained. Later on, when the 

 dust was once moving with the atmosphere, the distribution of 

 course was very much slower. If the dust came from Karakatoa, 

 such a difference in the rapidity of the distribution at the 

 beginning, and afterwards could not be accounted for. Besides it 

 seems extraordinary that in connection with smaller eruptions no 

 traces of after glow, even in the nearest vicinity of the Volcano 

 (Naples), has ever been observed. The long duration of the after 

 glow, which can even now be observed proves that the dust must 

 have been there originally in such quantities that a tellurie origin 

 does not appear at all probable. 



I therefore agree with Professor Smith that the dust is of 

 cosmic origin. But a question now arises which Professor Smith 

 has not dwelt on, namely, whether there is any connection 

 between the great eruption in the Straits- Settlements and the 

 arrival of the cosmic dust cloud. 



It is hardly likely that the centre of distribution of the after- 

 glow that is of the dust in the air should coincide by chance with 

 the great eruption in space, and the appearance of the dust with 

 the eruption in time. If this coincidence did not occur by chance 

 there are two possible ways of accounting for it : either the 

 eruption was the cause of the appearance of dust or the appearance 



