140 



MICRO-SPECTROSCOPE AND POLARISCOPE [CH. VI 



for the ocular micrometer (§ 172). If one now uses daylight there 

 will be seen in the spectrum the dark Fraunhofer lines (Fig. 121 E. F., 

 etc.). 



4 



Fig. 123. Fig. 124. Fig. 125. 



Fig 123. (1). Section of the tube and stage of the microscope with the spectral 

 ocular or micro-spectroscope in position. 



Amid Prism (| 188). — The direct vision prism of Amid in which the central 

 shaded prism of flint glass gives the dispersion or separation into colors, while the 



