THE AMERICAN 



MONTHLY 



MICROSCOPICAL JOURNAL. 



Washington, D. C, Janqaby, 1885. No. 1. 



Vol. VL 



( !ulture-tubes for Micro-Organisiiis. 



In ii previous number of the Jour- 

 nal, (Vol. V, p. 183,) the methods 

 >f cultivating micro-organisms, as 

 conducted by Dr. G. M. Sternberg 

 and Dr. D. E. Salmon, were de- 

 scribed. The relative merits of gela- 

 tinous and fluid media, and the spe- 

 cial adaptability of each for specific 

 purposes were concisely stated in the 

 article by Mr. T. Smith, Vol. V, p. 

 1S5. We have now to present illus- 

 trations of the two tubes used by the 

 observers named. Having seen the 

 tubes in practical use in both labora- 

 tories, we can only testify to the effi- 

 ciency of either form, and there is no 

 apparent reason why one should lead 

 to any better results than the other. 

 It is purelv a matter of individual 

 preference which form shall be used, 

 governed no doubt in part by the na- 

 ture of the work to be done, and the 

 conditions under which it is con- 

 ducted. 



In the laboratory of the Depart- 

 ment of Agriculture both Dr. Salmon 

 and his assistant. Dr. Smith, who 

 have been using the tube devised by 

 the former for a long time, regard it 

 as the best and most convenient for 

 their work. Dr. Sternberg, on the 

 other hand, prefers his own for con- 

 venience as well as for economy. 



In the article by Dr. Sternberg, re- 

 ferred to above, he has stated the ad- 

 vantages of his tube, which is shown 

 in Fig. I. Without repeating the 

 statements there made, we can only 

 say that on the score of economy it is 

 to be most highly recommended. 

 The bulbs are easily blown by any 

 person with very little practice, so 

 that one has only to purchase the 



glass tubing, which any druggist can 

 supply. 



As Dr. Salmon has not yet had the 

 opportunity to state 

 the advantages of his 

 tube, which is rep- 

 resented in Fig. 2, we 

 take the liberty of quot- 

 ing from a private let- 

 ter received from him 

 several months ago. 

 He claims that it best 

 fulfills the following 

 requirements : — 



' I. Cultivation li- 

 quids are easily and 

 safely sterilized in it, 

 and may be safely pre- 

 served at any tempera- 

 ture for any length of 

 time. 



' 2. The contents are 

 easily accessible for in- 

 fecting with virus, or 

 for examination of the 

 cultivations at various 

 stages of growth. 



' 3 . Experience 

 shows that such in- 

 fection and examina- 

 tion can be accom- 

 plished with scarcely 

 any danger of contam- 

 ination from atmos- 

 pheric germs. 



' 4. For convenience Fig. 1.— Sternberg's 

 and facility of use I Culture Tube. 



have seen nothing approaching . it 

 which was equally safe from contam- 

 ination. 



' 5. The objection of expensiveness 

 is not one that should be considered 

 in this class of work ; but this item is 

 largely overcome by the fact that my 



