A DUST-FALL IN THE SOUTH-WEST OF ENGLAND 87 
their sum, after deducting water and organic matter. No. 1 
is an analysis made by Professor T. E. Thorpe of a sample 
of the recent dust-fall of February 22, 1903, taken from 
the roof of Bayham Abbey, Lamberhurst.^ No. 2 is an 
analysis of dust from Taormina collected by Sir Arthur 
Rucker and now preserved at South Kensington.^ No. 1 
contained 9-08 per cent, of water and organic 
i matter and 
No. 2 possessed 23-49 per cent. 
Taormina 
Bayham Abbey 
Dust. 
Dust. 
No. 1. 
No. 2. 
Per cent. 
Per cent. 
Silica . . . • • 
. 47-47 
50-53 
Alumina .... 
. 21-37 
20-18 
Ferric Oxide 
7-94 
7-23 
Cobalt Oxide 
•42 
— 
Lime . . . • • 
8-16 
9-50 
Magnesia .... 
2-89 
2-04 
Sodium • Oxide 
3-38 
1-27 
Potassium Oxide . 
3-56 
2-53 
Carbonic Acid 
4-81 
6-72 
100-00 
100-00 
It is interesting to compare the foregoing results with 
the following analysis made by Gibbs about half a century 
ago of dust which fell on a ship in the Atlantic Ocean. After 
deducting 18-53 per cent, of water and organic matter we 
have — 
Per cent. 
Silica ........ 45-58 
Alumina ....... 20-55 
Ferric Oxide ... . . . . . 9*39 
Manganese Oxide ...... 4-22 
Calcium Carbonate . . . . . .11-77 
Magnesia ........ 2-21 
Potash ........ 3-64 
Soda .... ... 2-33 
Cupric Oxide ... ... -31 
100-00 
Professor T. E. Thorpe says that in sample No. 1 the 
1 Nature, vol. Ixviii. p. 54. 
2 Ibid. p. 222. The dust may be seen in the Geological department 
of the South Kensington Museum. 
