DUST STORM. 83 



fallino^ on the decks of ships many miles off the coast. A 

 late shower in the south of France, which was very exten- 

 sive, the microscope shows was from this cause. Dust 

 showers of volcanic ashes are also frequently met with in 

 volcanic countries, even hundreds of miles from volcanoes. 

 Such a shower occurred at Guayaquil in July, 18G9, which 

 Avas referred to the volcano of Pichunha, which rises im- 

 mediately above the plain of Quito. Other dust showers 

 are meteoric, frequently depositing a fine dark brown or 

 black dust in considerable quantities as in Canada, July 4, 

 1814, and at Montreal, Nov. 14, 1819. 



Red dust has also been deposited in like manner in snfii- 

 cient quantities for analysis, and is found like the dark 

 colored to contain a similar composition to meteoric stones. 

 Again there are sometimes microscopic animalcules, or 

 microscopic plants, but few of these are however on record. 

 Under some circumstances we have a comlii nation of ma- 

 terials as they frequently do in Prussia. In that country 

 on bright June daj^s there suddenly arises from the west- 

 ern horizon a dark gray offensive cloud which gradually 

 increases until it covers the whole sky and chansfes the 

 warm air into a cold stormy, and leaden atmosphere de- 

 positing a diist upon everything ; Avhich is found upon mi- 

 croscopic examination to be conqjosed of vegetable remains 

 charred, and minute particles of sand. The cause is that 

 the marsh lands of Hanover and the adjacent flat countries 

 are burned every summer in order to obtain a scanty crop 

 of buckwheat, from the almost barren soil. The windy 

 gusts caused by so much fire take up particles of sand 

 which, with the particles of vegetable matter carried up 

 with the smoke and wind, cause the showers referecl to. 



As a general thing all such phenomena can be traced to 

 their first cause, but in the shower of dust with snow first 

 spoken of as falling in Vermont, we are at once left in ob- 

 scurity. For a thousand miles in either direction the 

 ground was covered with snow. It was in fine, midwinter 

 and no fires were raging on the continent, or at least I 

 can get no trace of any. It is thousands of miles from any 



