21 



Macfadyen (1900) exposed vegetative and spore forms 

 of 10 kinds of l)acteria {hacilU, spirilla, staphylococci and 

 a pliotohacterium) to liquid air for 20 hours. The cultures 

 were either in broth or on solid media (gelatin, agar, 

 potato). No effect whatsoever was observed; all the 

 physiological properties : curdling of milk, fermentation 

 of sugar, indol production, pigmentation, pathogenicity 

 and photogenicity, appeared to be normal. 



In another experiment, Macfadyen liquefied the air of 

 his laboratory and cultured the bacteria present in it ; he 

 found several species of hacilli, cocci and sarcinae. The 

 temperature during the liquefaction of the air reached 

 about -210°. 



Macfadyen and Rowland (1900a and 1902) left B. coli, 

 B. typhosus and Staphylococcus pyogenes aureus in liquid 

 air for 6 months. The bacteria, suspended in small loops 

 of platinum wire or on cotton-wool swabs, were directly in 

 contact with liquid air. No impairment of vitality was 

 observed in any of the organisms. 



Lipman (1937) exposed for 48 hours to the temperature 

 of liquid air bacteria in the actively growing state. The 

 organisms were cultivated on agar slants in test tubes. 

 The latter were immersed in liquid air after having been 

 sealed. The 9 species of bacteria experimented upon sur- 

 vived and 8 of them presented an abundant growth. Par- 

 ticular attention was given to the choice of the species in 

 order to exclude the possibility of spore formation. 



Macfadyen and Rowland (1900b) observed no sign of 

 injury on various bacteria left for 10 hours, in sealed 

 tubes, in liquid hydrogen. 



De Jong (1922) summarizing the results of Beek (1919) 

 and Ongkiehong (1922), says that B. coli, B. faecalis 

 alcaligenes, B. lactis aerogenes, and the bacteria of 

 typhoid, of paratyphoid A and B, and of enteritis, resisted 

 equally well exposures to temperatures of - 20°, - 190° 

 and -253°. 



Kadisch (1931) found that B. coli (in 0.85% NaCl 

 solution) could resist - 252° (liquid hydrogen) for 3 hours, 



