No. 51423. 



Microscopes and Auxiliary Apparatus. 



537 



54 415. 1 : 3. 



a graduation of 360; it can easily be rotated and rapidly returned to the zero position. Two blow- s. d. 



tubes can be fixed to the stage for cooling the preparations, a rapid and fine temperature regulation 



being rendered possible by this means. Three mirrors are used as polarisers; the illuminating mirror 



is arranged to rotate so that rapid change is possible from direct to parallel, polarised illumination. 



The burner has a regulating air and gas lead. The tube possesses a rack and pinion coarse focussing 



and micrometer screw fine focussing. 



Supplied with the instrument are two burners, two blow-pipes, one blue glass, three plano- 

 convex lenses as cover glasses (for determining the refractive index), one heater, one double bellows, 

 and one mahogany case for storing the instrument. 



Projection Microscopes as suggested by Lehmann: see No.. 51,057 51,061, p. 183. 



54,410. Mineralogical Stand, with tongs objective changer having three inset rings, achromatic 

 objectives Nos. 1, 3 and 6, oculars I and III, micrometer ocular II, also gypsum and 

 mica plates l / t wave-length 



The coarse focussing is secured by rack and pinion, and the fine by micrometer screw. The tube 

 has a graduation and a centering head with locking gap for taking gypsum and mica compensators. 



The tube analyser can be switched in and out of the path of the rays. The condenser and 

 polariser can be raised and lowered by a lateral screw. The change from converging to parallel light 

 is done by a quarter-turn of a lateral knob and the polariser can be taken out of the condenser lens. 

 The stage is graduated in 1 /, and permits of reading by vernier accurately to 1 / 10 - The surface of 

 the stage has a position-finding graduation. 



54.415. Large Preparation Stand, Figure, with heavy horse-shoe shape base, stage 

 100 xlOO mm with glass plate and hollowed metal trough; focussing by rack and pinion; 

 cheeks for supporting the hands. With movable mirror, lens system comprising 

 3 aplanatic magnifiers, for magnifications of 8, 14 and 20 



54.416. - - idem, with 2 aplanatic magnifiers for 8 and 14 diameters, and with a Preparation 

 System consisting of 3 aplanatic lenses (as objective) and an achromatic ocular, for 15, 

 20 und 30 diameters when not using ocular, and 40, 60 and 100 with use of ocular. 



Auxiliary Apparatus for Microscopes. 



54.417. Micrometer Ocular, with lateral slot for inserting the micrometer 



54.418. Ocular Glass Micrometer, for inserting in the ocular, 5 mm = 100 divisions 



54.419. --idem, 5 mm = 50 divisions 



54.420. Object Micrometer, 1 mm = 100 divisions, glass graduation 



54,421. Ocular Net Micrometer for counting objects strewn over the field of view, in mount, 

 distance apart of lines 0.5 mm 



54,422. Indicating Apparatus after Abbe 



54,423. Microtome, simple pattern, for freehand cutting 



The specimen is clamped in a cylinder which can be screwed 10 mm below the surface of the 

 table. One graduation of the micrometer screw is equivalent to raising the object 0.01 mm. The blade 

 of the knife is guided over the glass table, the diameter of which is 70 mm. 





Cl. 5933. 



19. 0.0 



4. 0.0 



5. 0.0 



0.12.0 

 0. 4.0 

 0. 3.0 

 0. 6.0 



0. 5.0 

 2. 2.0 

 0.18.0 



