= 3 o 



Nos. 25 and 26. Ordinary Condenser in sliding tube, No. 25: double 

 lens formation (Fig. 9 a ), num. Ap. 1.20, equivalent focal length about 12 mm; 

 No. 26: triple lens formation (Fig. 9 b ), num. Ap. 1.40, equivalent focal length 

 about 8 mm. 



Nos. 27 and 28. *Swing-OUt Condenser with iris-cylinder diaphragm. 

 Fig. 10; No. 27: double lens, and No. 28: triple lens formation. 



This form of condenser was introduced by us in 1894 (see Zeitschr. f. wiss. 

 Mikrosk., vol. XI, 1894, pp. 433 440). The apparatus offers the advantage <>f 

 having the condenser and the iris-cylinder diaphragm combined. Fig. 10. By 

 the aid of a suitable mechanism the condenser system may be folded clear of 

 the carrier of the iris-cylinder diaphragm and swung aside so as to facilitate, by 

 simple means, a change from illumination by mirror and condenser to that by 

 mirror alone. For details of construction see Directions for Use of ABBE 

 Illuminating Apparatus. 



In subsequent orders for condensers specified under Nos. 2528 

 the factory number of the stand should be stated. 



Vig. 10. 



Swing-out Condenser with Iris-cylinder Diaphragm, 



withdrawn from the sliding sleeve and condenser swung out. 

 ( :! / 4 Full Size.) 



Ordinary Condenser in sliding tube 



Double lens formation, num. Ap. 1.20 . . . . 

 Triple lens formation, num. Ap. 1.40 .... 



Swing-out Condenser with Iris-cylinder Diaphragm 

 Double lens formation, num. Ap. 1.20 .... 

 Triple lens formation, num. Ap. 1.45 .... 



Marks Codnoord 



20. I'apaga 

 25. 1'apelear 



45. 

 50. 



1'aprleta 

 Papenro 



