1884.] 



MICROSCOPICAL JOURNAL. 



186 



ilown ' of a stock solution. Even if 

 such accidents were not of common 

 occurrence, the method I recommend 

 would be preferable on the score of 

 economy of time and material and of 

 ease of manipulation. The advan- 

 tages claimed, briefly stated, are as 

 follows : — 



The small flasks employed are 

 made in the laboratory, from glass 

 tubing, very expeditiously and at 

 small expense. 



Each flask contains a sufficient 

 amount of nutrient fluid and of oxy- 

 gen to insure a vigorous and abun- 

 dant development of any aerotic mi- 

 cro-organism introduced as seed. 

 The bacilli readily form spores in 

 these flasks. 



When properly sterilized the en- 

 closed culture-medium remains un- 

 changed indefinitely, and the little 

 flasks, ready for use at a moment's 

 notice, may be packed away in 

 drawers or boxes for years, if desired, 

 and may be conveniently transported 

 from place to place. 



The inoculation of one flask with 

 micro-organisms contained in an- 

 other, or with a drop of blood from 

 the veins of a living animal, etc., etc., 

 is effected expeditiously and with 

 perfect security from contamination 

 by atmospheric germs. 



Small amounts of fluid may at any 

 time be withdrawn from one of these 

 flasks for microscopic examination 

 without the slightest danger of intro- 

 ducing foreign organisms, and thus 

 destroying the purity of the culture. 



Finally, these little flasks take the 

 place of a syringe when an inocula- 

 tion experiment is to be performed, 

 the contents being forced beneath the 

 skin, or into one of the cavities of a 

 living animal, by applying gentle 

 heat to the bulb, thus causing the en- 

 closed air to expand, and forcing the 

 fluid contents through the capillary 

 neck of the flask. 



The method having been described 

 in detail in my paper already referred 

 to (see report A. A. A. S. for 1881) 

 my principal object at present is to 



give a practical demonstration of its 

 advantages over other methods of 

 cultivating micro-organisms in fluid 

 media. 



o 



Remarks on Fluid and Gelatinous 

 Media for ( ultivatin|| Micro- 

 oi^anisnis, with Description of 

 Salmon's New Culture-tube and 

 Demonstration of the Process of 

 using it. 



The above was the title of a paper 

 read by the Editor of this Journal, 

 but written at his request by Mr. 

 Theobald Smith, the assistant of Dr. 

 Salmon in his laboratory. A cut 

 showing the construction of the tube 

 will be given, if possible, next month. 

 The paper was as follows : — 



Much has been said of late concern- 

 ing the advantages of a solid substra- 

 tum over a liquid medium in the cul- 

 ture of the Schizomycetes or so-called 

 bacteria. This is no doubt due to its 

 very successful employment by Dr. 

 Koch in the study of tuberculosis, 

 and more recently of cholera, and his 

 own oft-repeated statements as to its 

 superiority. He has, however, em- 

 ployed liquid media for bis cultures of 

 the tubercle-bacillus, and is now 

 studying the comma-bacillus, in a de- 

 coction of meat. In fact, he says that 

 it flourishes best in fluids which do not 

 contain too little nutrient material. 

 (See Deutsche Med. Wochenschrift ^ 

 1884, p. 503.) 



Many bacteria naturally live in 

 fluids, such as the blood in case of 

 disease, in stagnant water, etc. The 

 life-history of such forms can never be 

 traced completely without resorting 

 to liquid cultures, approximating in 

 physical and chemical properties the 

 natural medium of the microphytes. 

 Thus, the swarming stage of bacteria 

 can only assert itself in a fluid, and 

 the peculiarity of many species to 

 collect in the form of a membrane on 

 the surface of liquids at a certain pe- 

 riod of their life can express itself 

 only very indirectly or not at all upon 

 a layer of gelatin or blood serum. 



