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SUMMARY OF CURRENT RESEARCHES RELATING TO 



Vienna. It is differentiated from ordinary Microscopes by making the 

 object-stage swing round the tube-holder. When the stage has been 

 rotated through 180°, a movable bent object-holder can be brought 

 into position between the mirror and objective, and on its free end is 

 applied an extensible collar bearing a cork. The object, on a pin, is 

 set in this cork, and, by the variety of movements possessed by the 

 arrangements, can be brought into any desired position in front of the 

 objective. For the examination of opaque objects, a second mirror 

 fastened on the tube-holder furnishes the required incident light. The 

 instrument might also be used for botanical objects, or for any others 

 which should be viewed from all sides. 



Hollick's Naturalists' Microscope. — This instrument (fig. 79) is 

 a modification of R. and J. Beck's well-known Star Microscope, and 



Fig. 79. 



was made to the drawings of A. Hollick, who wished to have : first, 

 the utmost compactness ; and secondly, good illumination for opaque 

 objects. 



The former of these objects is obtained by making the bottom of 

 the Microscope case the base of the instrument, and by folding the 

 Microscope down on to it on the principle of R. and J. Beck's Popular 

 Microscope ; but the lower end of the pillar, instead of dropping into 

 a series of holes, slides in a slot, and can be clamped in any position, 

 so that any desired inclination can be imparted to the Microscope. 

 Owing to its large base, the instrument, though light, is very stable. 



The second object is attained by swinging the mirror on a centre 

 above the stage approximately level with the object ; that is to say, on 

 an arm of such length that the lamp flame is focussed on to the object 



