I. MICROSCOPES. 907 



5. Identity of illumination in each tube. 



6. The use of the highest powers rendered possible by the projection of 

 the prisms beyond the body of the instrument into the objective. 



354:0a. New Binocular Microscope. Henry Crouch, 



This instrument has a concentric rotating stage provided with adjustments 

 for centering to the highest powers that can be applied. The sub-stage is also 

 of new construction, being detached from the stand by means of a horizontal 

 slide, and leaving the space underneath the stage entirely clear for greater 

 convenience in the use of ordinary oblique illumination. 



3540b. Newly arranged Binocular Microscope. 



Henry Crouch* 



This is of somewhat similar construction to the above, but not so expensively 

 finished ; with and without sub-stage. 



3540c. New Premier Binocular Microscope for Bota- 

 nical and Il'istological Work. Henry Crouch* 



3540e. Students 9 Binocular Microscopes of Old and 

 New Pattern. Henry Crouch* 



New Educational Monocular for Botanical and Histo- 

 logical Work. Henry Crouch* 



3541. Student's Microscope. James How fy Co. 



3542. Popular Binocular Microscope. 



James How $ Co* 



3543. Educational Microscope." With two object 

 glasses, two eyepieces, condenser, &c., in mahogany box. Suitable 

 for biological, histological, and physiological research. 



M* Pillischer. 



3544. " Student's " or Educational Microscope." 

 With three object glasses, three eyepieces, condenser, polarising 

 apparatus, animalcule cage, stage-forceps, &c., in mahogany case. 

 Suitable for clinical and biological research, &c. M. PilliscJier* 



3545. " New College Microscope." James Swift* 



In this microscope the optical tube slides through a fitting lined with velvet 

 for smoothness of action. The fine adjustment has direct central movement, 

 and is so constructed as not to be deranged by constant use. The diaphragm 

 is flush with the surface of the stage, thus leaving the tube-fitting free under- 

 neath for the use of apparatus, and, if required, the diaphragm can be used in 

 conjunction with any of the stage accessories. 



3546. " University Student's Microscope," in a cheap 

 and efficient form, especially designed for medical and botanical 

 students. James Swift* 



3547. Crane Arm Binocular Microscope, with newly 

 contrived concentric stage and adjustable object holder moving 

 upon glass bearings. All the fittings of this microscope are made 

 self-compensating for wear. James Swift. 



