A LABORATORY COURSE 
BACTERIOLOGY. 
CHAPTER I. 
MICROSCOPIC EXAMINATION OF BACTERIA. 5 
I. MANIPULATION OF THE MICROSCOPE. 
1. Examine mounted slides of bacteria with the 
low-power (# inch) and high-power (4 inch) objec- 
tives and with different eyepieces. 
2. Manipulate the condenser, diaphragm, and 
mirror, in order to ascertain what combination 
gives the best result. 
3. (a) Affix the oil-immersion lens (7; inch) to 
the microscope. 
(4) Place a drop of immersion oil on the cover- 
glass. 
(c) Bring the lens to a focus in the drop of oil. 
(2) Again manipulate condenser, diaphragm, and 
mirror to determine what combination now is best. 
il. MEASUREMENT OF BACTERIA. 
The most accurate method of measurement is 
by photography ;' but as this requires special appa- 
1 See Appendix, page 163. 
ll 
