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XVI. — On a Septio Microbe from a high altitude. The Niesen 



Bacillus. 



By G. F. DoWDESWELL, M.A., F.E.M.S., F.L.S., &o. 



{Bead 8th April, 1885.) 



At the present time, when the functions of micro-organisms in 

 all the provinces of nature, more especially in relation to disease, 

 are exciting such general interest, their occurrence in the atmosphere 

 has engaged renewed attention. 



The systematic study of the particulate constituents of the 

 atmosphere commenced with Ehrenberg, though in the previous 

 century Leeuwenhoek had made the first recorded observations 

 upon Bacteria, and shown their occurrence in rain-water. Ehren- 

 berg examined dust from various situations in extensive series of 

 observations, and particularly with reference to the outbreak of 

 cholera in 1848, though with negative results, but found that 

 numerous forms of organic life, both vegetable and animal, as he 

 regarded them, were present in dust of the most varied situations ; 

 he recognized the occurrence of bacteria, which he termed infusoria, 

 in rain-water that was allowed to stand, but could not detect any 

 in the fresh drops, in dew, or in the atmosphere. 



After that tune the subject was pursued by numerous observers, 

 till towards the year 1859 the promulgation of the vital, or " germ," 

 theory of fermentation and putrefaction by Pasteur, aroused the 

 controversy respecting spontaneous generation, so fertile in results, 

 in the French Academy, and this induced the first systematic 

 observations of Pouchet, the foremost of the Abiogenetists, and 

 those of Pasteur himself, upon atmospheric germs, followed by a 

 constant succession of observers, amongst whom, however, the most 

 diverse views as to the occurrence of organic germs in the air have 

 prevailed till quite recently, when the question has been finally set 

 at rest, firstly by the systematic observations of Dr. Miflet, of Kiew, 

 made in the Botanical Institute of Breslau in conjunction with 

 Professor F. Cohn,* with the object of determining whether the 

 microbes that produce fermentation and putrefaction are veritably 

 contained in the atmosphere, or whether they are not derived 

 exclusively from water or contact with contaminated surfaces, as 

 previous experiments, by Prof. Cohn himself and others, seemed to 

 indicate. 



The result of these observations was to show clearly that by 

 aspirating the air of different localities through cultivating fluids of 

 suitublc constitution, various species of bacteria or their germs were 

 introduced, and developed when placed in the incubator at tho 



♦ Beitr. Biol, Pflanz., i. (1879) p. 113. 



