205 



Notes on Supposed Volganiig Dust from the 

 Northern Territory. 



By Professor Rennie, M.A., D.Sc, and A. J. Higgin, F.I.C- 



[Read August 4, 1903.] 



The following is a portion of a letter received by us from 

 Sir Cliarles T'odd in December, 1902 : 



"I have just received ithe enclosed telegram from Mr^ 

 Christie, lighthouse keeper ait Point Charles, who has collected 

 some of the supposed volcanic dust which has. been resting on 

 Northern Australia for some weeks past, and is supposed to 

 have come from Martinique." 



The telegram referred to^ in the above extract is as follows : 



''Profiting by thei experiments made by Mr'. Bleeser in catich- 

 ing volcanic dust, it occurred tO' me that the lighthouse 

 windows would be an ideal catchment^ and I had noitdced before 

 I left that they were becoming dusty. On arrival here, how- 

 ever, I found that 115 points of rain had faillen, which, of 

 course, eliminated all signs of dust, washed the glass clean, and 

 effectually laid any local dust. This was Saturday, November 

 22nd. Noted on the 23rd that smoke with the same peculiar 

 smell was about, but not so thick; 24th still smoky. Tried 

 window panes, and could detect a little' dust on white rag. 

 25th still smoky. Thinking rain would probably fall, decided 

 to do as followsi: Took 4 gallons water, jug, washbasin, and 

 empty bucket;. Placed washbasin under window ledge, and 

 with jug poured water on, thei top plane. This ran down 

 the three panes 10 ft., and was caught in the basin and transh 

 ferred to bucketi, and so' on. I thus washed ovei^ 300 superficial 

 feet of glass with running water only ; the resailt a bucket of 

 dirty water. This was covered, and stood to setitle for two 

 daysi ; the water syphoned off. The bottom half a pint placed 

 in a glass tumbler, and settled for one day; the remainder 

 of water syphoned, and the tumbler stood near the fire till 

 contents evaporated to dryness. The residue, only a few" 



grainSi, I am sending to you. It looks very like volcanic ash. 

 I may mention that during thisi period of dust or smoke! catch- 

 ing the wind was from north-west and north-east, and once 

 only for a short time east. The lighthouse windows are 120 

 ft. above sea level, and all these winds blow directly off the 

 sea. The nearest land north-west would be Bathurst Islands,. 



