554 SUMMARY OF CUKKENT RESEARCHES RELATING TO 



extreme the flatness of field and the wide angle of same are extraordinary. 

 With a telescopic objective of 7-in. focal length and a micro-objective of 

 1-in. focal length, a magnification of forty-five diameters is obtained. 

 With such an arrangement Jupiter and four of his moons were observed 

 with astonishing clearness during June. The best general results were, 

 however, obtained with a li-in. micro-objective, which, so far, has given 

 the brightest and most clearly defined image. With this objective the 

 magnification was about twenty-seven diameters. 



The attachment is made to fit into the diaphragm or Abbe illuminator 

 rim or under-fitting d on the stage or sub-stage. By means of this com- 

 bination when the telescope attachment is in place any degree of 

 magnification from twenty to forty-eight diameters may be obtained by 

 adjustment of the draw-tube and eye-piece to focus the micro-objective. 



The only necessary alteration to the Microscope is to remove the stop 



Fig. 93. 



screw or bar so as to allow the eye-piece to be lowered below the 

 horizontal to admit of observing objects at an elevation. For astro- 

 nomical purposes and to facilitate observation at high angles, such as the 

 moon or stars at or near the zenith, a reflector /; is attached to the tube a. 

 This reflector is ground optically correct for the purpose and is mounted 

 upon a universal joint so as to be adjustable in all directions. By 

 means of this reflector objects overhead or at high angles may be com- 

 fortably observed. When the micro-telescope is employed for terrestrial 

 observation a tube c is employed to screen light from the gap between 

 the stage and the micro-objective. 



The combination forms an exceedingly compact telescope of fibout 

 15 in. in length, and the mechanical adjustments are available for 

 focusing. To further facilitate observation, however, the tripod stand 

 is secured to a special rotatable base mounted on a pedestal or tripod, 

 the rotatable base being movable by means of suitable screw adjustments 



