Ch. VI] avoidance of INVERSION; ERECT IMAGES 



175 



Test the correctness of the directions by using a preparation with 

 the letters a, k, on the cover-glass (§ 277, fig. 105). 



§ 282. Erect images with an objective or an objective and an 

 amplifier and a prism or 45° mirror. — Place the specimen on the 

 10 CENTIMETER RULE 



a^aH HaxaiMixNaD ox 

 ajuH HaT3MiTvrao oi 







10 CEMJiiyiEXEB BnrE 



Fig. 106. I, 2, 3, 4, Erect and Inverted Images or the Metric Scale. 



(From Optic Projection). 



I. Erect image. 2. Inverted image. 3. Mirror image. 4. Inverted mirror image. 



stage wrong edge up and with the cover-glass toward the objective. 



The image will be erect on the opaque drawing paper. Test with 



the lettered specimen (fig. 105). 

 § 283. Erect images with an objective and an ocular. — 

 (i) Opaque drawing paper. Place the specimen on the stage 



