29 



No. 21. The Cylinder-Diaphragm, Fig. 5K A sliding tube fitted with 



v5 stops yielding apertures of 1 mm, 3 mm and (> mm diameter. 



Xo. 22. The * Iris-Cylinder Diaphragm. In order to obtain a gradual 

 variation of the illumination when working without a condenser, we have con- 

 structed the iris-cylinder diaphragm. The laminae forming the apertures 

 of these diaphragms are arched in the shape of a cupola so that, when the iris is 

 entirely closed, their edges almost touch the lower side of the object slide. 



The cylinder-diaphragm Xo. 21 and the iris-cylinder diaphragm No. 22 can 

 also be employed in the sliding sleeve of Stand V. 



In subsequent orders for cylinder and iris-cylinder diaphragms 

 the factory number of the stand with which they are to be used 

 should be stated. 



No. 23. The Iris-Diaphragm. The ordinary iris-diaphragm, as always 

 supplied with the illuminating apparatus, may also be obtained independently. 



No. 24. Diaphragms for dark-ground illumination. Since a rational 



employment of dark-ground illumination is only possible , when the 

 dimensions of the stop are exactly adapted to the aperture of both objective and 

 condenser, the various stops are only supplied to special order. 



For the homogeneous immersion systems we will in future supply only a star-disc with 

 central stops to be suspended in the objective mount above the lenses. Stopping down the illuminating 

 cone of rays is thus not performed by means of a central stop in the diaphragm carrier, but through 

 the ordinary iris-diaphragm. 



In subsequent orders should be mentioned the objective and condenser for 

 which the central stops are required. (See directions for the ABBE Illuminating 

 Apparatus.) 



Objectives with correction collars are unsuitable for the employment in 

 illumination. 



Cylinder-diaphragm with 3 stops 



Iris-cylinder Diaphragm 



Iris-diaphragm for the diaphragm carrier ........ 



Stops etc. for dark-ground illumination 



a) Star-disc with button to support central stop 



b) Central stop each 



c)- Diaphragms to screw into the mounts of Achromatic ob- 

 jectives each 



d) Diaphragms to slip into the mounts (from above) of Apo- 

 chromatic objectives each 



e) Star-disc with central stop for homogeneous immersion ob- 

 jectives each 



Marks 

 4. 



14- 



10. 



Codeword 

 Pantografo 

 Pautnflo 

 Paiizudo 



0.50 Papado 



1. Papagallo 



O.CO Papalina 



1.50 Papanatas 



3. Papasso 



