RULES FOR USE OF COMPOUND MICROSCOPE. 113 



move the tube up by turning the coarse 

 adjustment until the object is seen as 

 clearly as possible. Be careful never to 

 push the tube down so the objective 

 touches the slide. 

 7. In examining a slide, focus the tube by 



means of the fine adjustment. 

 III. To use the high-power objective. 



1. Place the slide upon the stage and focus 



upon it with the low -power objective as 

 directed in II above. 



2. Turn the mirror so the concave surface 



faces the source of light. Looking 

 through the tube, move the mirror about 

 until the field of the microscope has the 

 best illumination. 



3. Place the eye at the level of the stage and 



carefully turn the nose-piece so the high- 

 power objective is brought into position 

 above the hole in the stage. If the 

 lower end of the objective touches the 

 cover-glass, turn the fine adjustment 

 screw in a direction opposite to that of 

 the hands of a clock. 



4. When the objective is in position look at 



the object through the microscope and 

 focus slowly with the fine adjustment- 

 screw until the image is clearest. Take 

 great care, as directed in 3 above, to see 

 that the objective does not touch the 

 cover-glass. 



5. After using the high-power objective, turn 



