7 6 



MICROSCOPICAL EXAMINATION OF BACTERIA 



by touching the loop on one of the drops of 

 moisture which are usually to be found con- 

 densed on the interior of the glass tube, or by 

 dipping it into the condensation water at the 

 bottom; at the same time care must be taken 

 in the case of cultures on solid media to avoid 

 touching either the medium or the growth.) 



7. Remove a small portion of the growth by 

 taking up a drop of liquid, in the case of a fluid 

 culture, in the loop ; or by touching the loop on 

 the surface of the growth when the culture is on 

 solid medium; and withdraw the loop from the 

 tube without again touching the medium or 

 the glass sides of the tube. 



8. Replace the cotton-wool plug in the 

 mouth of the tube. 



9. Replace the tube cultivation in its rack or jar. 



10. Mix the contents of the loop thoroughly with 

 the drop of water on the 3 by i slide. 



11. Again sterilise the loop as directed in step 4, 

 and replace it in its stand. 



12. Remove a cover-slip from the glass capsule by 

 means of the cover-slip forceps, rest it for a moment 

 on its edge, on a piece of filter paper to remove the 

 excess of alcohol, then pass it through the flame of the 

 Bunsen burner. This burns off the remainder of the 

 alcohol, and the cover-slip so "flamed" is now clean, 

 dry, and sterile. 



13. Lower the cover-slip, still held in the forceps, 

 on to the surface of the drop of fluid on the 3 by i 

 slip, carefully and gently, to avoid the inclusion of air 

 bubbles. 



14. Examine microscopically (vide infra). 



During the microscopical examination, stains and 

 other reagents may be run in under a cover-slip by 

 the simple method of placing a drop of the reagent in 

 contact with one edge of the cover-glass and apply- 



