45 



fig. 19. 

 Sliding Objective-changer. 



33. 



a: tube-slide; b: objective-slide with objective attached; c: in section. 

 (Full Size.) 



centring adjustment in the direction of the slide, while an endless screw (at 

 right angles to the first-mentioned and, like it, regulated by a watch key) effects 

 the centring of the objective at right angles to the slide. 



Objectives having their mounts so adjusted as to be approximately in focus 

 when changed can also, by means of the screw-collar on the objective slide, be 

 accurately focussed and then permanently fixed in their proper position by a 

 locking nut. 



We are prepared, at request, to adjust in our Works with the greatest 

 care several objectives to be used on a revolving nose-piece or with sliding ob- 

 jective-changers to one focal plane, with the exception of the systems a, aa, a* 

 and the immersion systems, if objectives and objective-changers be obtained at 

 the same time, but we must expressly remark that this adjustment 

 is accurate only when the correct tube-length is maintained. 



Wos. 54 and 55. For the convenient safe-keeping of objectives with ob- 

 jective-slides attached to them, we supply, when requested, special cases in 

 various sizes. The most usual forms are the leather case No. 54 for 3 objectives 

 with their slides, and the mahogany case for 6 objectives with their slides. 



Leather case for 3 Objective -slides and Ob- 

 jectives 



Mahogany case for 6 Objective-slides and Ob- 

 jectives 



Marks Codeword 



6. Parhilera 



15. Parida 



