COLLINS'S BINOCULAR STAND. 



107 



The limb that carries the body, stage, sub-stage, and 

 mirror, is in one piece, with a machine-planed groove 

 from end to end, thus ensuring considerable accuracy. 

 A rack-work movement of 6 in. is given to the body, 



FIG. 60. Coliins's Binocular Microscope. 



allowing the use of low-power objectives, so much 

 appreciated in binocular microscopes. The Wenham 

 prism box is made on the Harleyplan, enabling the 

 polariscope to be brought into action without removal 

 of the objectives or putting the same out of focus. 



