Ludwig Tesdorpf, Stuttgart. 



125 



measuring ocular constructed on Reichenbach's principle with adjustable web: 

 objective of 32 millimeter diameter magnifying 36; reversion level with sensi- 

 bility of 12 sec. 



3. Distance scale A: connected with the telescope, reading to milli- 

 meters to both sides of the zero point; the divisions on the right hand side 

 of the zero point are used when the telescope is placed in its usual position, 

 the divisions on the left hand side are to be considered when the instrument 

 is used as a transit- theodolite. 



Note: Upon this scale the distance pointer B fitted with automatic spring 

 stop is made to slide easily. With reductions of 1 : 1000 distances of 210 to 

 230 meters can be taken, with reductions of 1 : 2000 these distances may, 

 therefore, vary from 4:20 to 460 meters. 



Fig. i. 



4. The pointer B, which slides along the distance ruler A, is fitted with 

 two verniers. The lower vernier serves to adjust the distance read off the 

 distance rod, the latter being throughout divided in decimeters and centi- 

 meters. The upper vernier is made to rotate and is fitted with special vertical 

 correction and is so arranged that with any position and inclination of the 

 telescope the divisions of the projection triangle R are automatically closely 

 approached by the vernier as soon as the triangle is raised. 



Note: When the vernier is on the zero point of the scale A the edge of 

 the upper vernier coincides exactly with the center of the telescope axis. 



5. Scale F affixed to P, reading to 1 millimeter, for taking the hori- 

 zontal projection of the oblique distance adjusted by scale A. 



