28 



The Microscope 



Figs. 27, 28, 29, and 30. Setting up a medical microscope. Fig. 27. The mirror is 

 moved until the XlO objective is filled with light. Fig. 28. The neutral density filter 

 is put in place and a slide focused with the coarse adjustment. Fig. 29. The eyepiece 

 is removed and the mirror and lamp are adjusted until the filaments are seen. Fig. 

 30. A piece of paper is held just in front of the mirror and an image of the filaments 

 focused on this paper. 



3. (Fig. 29.) Shut down field iris and remove eyepiece. Look down 

 the tube, with the eye about 2 in. away. Manipulate mirror, position of 

 lamp, and tilting device of lamp, until the lamp filaments are centered 

 in the objective. 



4. ( Fig. 30. ) Open field iris and lay a sheet of white paper on the 

 mirror. Use the focusing device of the field condenser to throw an image 

 of the lamp filament on the paper. A slight shift of the focusing device 

 will then bring this image into focus on the substage iris [Fig. 26(1)]. 



5. ( Figs. 31 and 32. ) Close the field iris and focus an image of the 

 field iris onto the object with the substage [Fig. 26(3)]. If the image is 

 not central, adjust the mirror. Make sure that the object is still in focus. 

 Open the field iris until it just delimits the field [Fig. 26(4)]. 



